diff --git a/test/parallel/test-child-process-bad-stdio.js b/test/parallel/test-child-process-bad-stdio.js
index 45294d7d82d4f6..1f382e2966043d 100644
--- a/test/parallel/test-child-process-bad-stdio.js
+++ b/test/parallel/test-child-process-bad-stdio.js
@@ -1,5 +1,5 @@
 'use strict';
-// Flags: --expose_internals
+// Flags: --expose-internals
 const common = require('../common');
 const assert = require('assert');
 const cp = require('child_process');
diff --git a/test/parallel/test-child-process-exec-kill-throws.js b/test/parallel/test-child-process-exec-kill-throws.js
index d6a0d4da19eae7..fbc9677f531068 100644
--- a/test/parallel/test-child-process-exec-kill-throws.js
+++ b/test/parallel/test-child-process-exec-kill-throws.js
@@ -1,5 +1,5 @@
 'use strict';
-// Flags: --expose_internals
+// Flags: --expose-internals
 const common = require('../common');
 const assert = require('assert');
 const cp = require('child_process');
diff --git a/test/parallel/test-child-process-http-socket-leak.js b/test/parallel/test-child-process-http-socket-leak.js
index 9b284f285c4572..cae4b051bc2b35 100644
--- a/test/parallel/test-child-process-http-socket-leak.js
+++ b/test/parallel/test-child-process-http-socket-leak.js
@@ -1,4 +1,4 @@
-// Flags: --expose_internals
+// Flags: --expose-internals
 
 'use strict';
 
diff --git a/test/parallel/test-child-process-spawnsync-kill-signal.js b/test/parallel/test-child-process-spawnsync-kill-signal.js
index 0c8f4a6d465b4f..6d14f24724bb2b 100644
--- a/test/parallel/test-child-process-spawnsync-kill-signal.js
+++ b/test/parallel/test-child-process-spawnsync-kill-signal.js
@@ -1,4 +1,4 @@
-// Flags: --expose_internals
+// Flags: --expose-internals
 'use strict';
 const common = require('../common');
 const assert = require('assert');
diff --git a/test/parallel/test-child-process-spawnsync-shell.js b/test/parallel/test-child-process-spawnsync-shell.js
index 0a20a490dd6cc4..0dd50cedd123b2 100644
--- a/test/parallel/test-child-process-spawnsync-shell.js
+++ b/test/parallel/test-child-process-spawnsync-shell.js
@@ -1,4 +1,4 @@
-// Flags: --expose_internals
+// Flags: --expose-internals
 'use strict';
 const common = require('../common');
 const assert = require('assert');
diff --git a/test/parallel/test-child-process-validate-stdio.js b/test/parallel/test-child-process-validate-stdio.js
index 5b0259f19bbd1f..ff214ee2d78262 100644
--- a/test/parallel/test-child-process-validate-stdio.js
+++ b/test/parallel/test-child-process-validate-stdio.js
@@ -1,5 +1,5 @@
 'use strict';
-// Flags: --expose_internals
+// Flags: --expose-internals
 
 const common = require('../common');
 const assert = require('assert');
diff --git a/test/parallel/test-child-process-windows-hide.js b/test/parallel/test-child-process-windows-hide.js
index 42bca6471ccdbc..1d9593c0a99242 100644
--- a/test/parallel/test-child-process-windows-hide.js
+++ b/test/parallel/test-child-process-windows-hide.js
@@ -1,4 +1,4 @@
-// Flags: --expose_internals
+// Flags: --expose-internals
 'use strict';
 const common = require('../common');
 const assert = require('assert');
diff --git a/test/parallel/test-constants.js b/test/parallel/test-constants.js
index 62c62b101a10a8..08d1f1dbcdd0ab 100644
--- a/test/parallel/test-constants.js
+++ b/test/parallel/test-constants.js
@@ -1,4 +1,4 @@
-// Flags: --expose_internals
+// Flags: --expose-internals
 'use strict';
 
 require('../common');
diff --git a/test/parallel/test-fs-open-flags.js b/test/parallel/test-fs-open-flags.js
index 80e54d169d5264..4c4b8039dca678 100644
--- a/test/parallel/test-fs-open-flags.js
+++ b/test/parallel/test-fs-open-flags.js
@@ -19,7 +19,7 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-// Flags: --expose_internals
+// Flags: --expose-internals
 'use strict';
 const common = require('../common');
 
diff --git a/test/parallel/test-http2-compat-socket.js b/test/parallel/test-http2-compat-socket.js
index 0db2876738c766..95bc42180ef8e9 100644
--- a/test/parallel/test-http2-compat-socket.js
+++ b/test/parallel/test-http2-compat-socket.js
@@ -1,4 +1,4 @@
-// Flags: --expose_internals
+// Flags: --expose-internals
 
 'use strict';
 
diff --git a/test/parallel/test-http2-socket-proxy.js b/test/parallel/test-http2-socket-proxy.js
index 17704e2fd9e3b7..3294cf7ccb9011 100644
--- a/test/parallel/test-http2-socket-proxy.js
+++ b/test/parallel/test-http2-socket-proxy.js
@@ -1,4 +1,4 @@
-// Flags: --expose_internals
+// Flags: --expose-internals
 
 'use strict';
 
diff --git a/test/parallel/test-icu-stringwidth.js b/test/parallel/test-icu-stringwidth.js
index e2f22941158578..66d75c4cbe2cb2 100644
--- a/test/parallel/test-icu-stringwidth.js
+++ b/test/parallel/test-icu-stringwidth.js
@@ -1,4 +1,4 @@
-// Flags: --expose_internals
+// Flags: --expose-internals
 'use strict';
 const common = require('../common');
 
diff --git a/test/parallel/test-internal-util-decorate-error-stack.js b/test/parallel/test-internal-util-decorate-error-stack.js
index 40fbf1d48caf20..b12d50bee79abc 100644
--- a/test/parallel/test-internal-util-decorate-error-stack.js
+++ b/test/parallel/test-internal-util-decorate-error-stack.js
@@ -1,4 +1,4 @@
-// Flags: --expose_internals
+// Flags: --expose-internals
 'use strict';
 require('../common');
 const fixtures = require('../common/fixtures');
diff --git a/test/parallel/test-os-checked-function.js b/test/parallel/test-os-checked-function.js
index e0758437fe873f..819cdf1794155f 100644
--- a/test/parallel/test-os-checked-function.js
+++ b/test/parallel/test-os-checked-function.js
@@ -1,5 +1,5 @@
 'use strict';
-// Flags: --expose_internals
+// Flags: --expose-internals
 
 require('../common');
 const { internalBinding } = require('internal/test/binding');
diff --git a/test/parallel/test-readline-interface.js b/test/parallel/test-readline-interface.js
index 0f96f8368b5d29..59a65e8ca2020e 100644
--- a/test/parallel/test-readline-interface.js
+++ b/test/parallel/test-readline-interface.js
@@ -19,7 +19,7 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-// Flags: --expose_internals
+// Flags: --expose-internals
 'use strict';
 const common = require('../common');
 
diff --git a/test/parallel/test-readline-tab-complete.js b/test/parallel/test-readline-tab-complete.js
index 5afa60e4dae9fd..d7a4bb7a9a0690 100644
--- a/test/parallel/test-readline-tab-complete.js
+++ b/test/parallel/test-readline-tab-complete.js
@@ -1,6 +1,6 @@
 'use strict';
 
-// Flags: --expose_internals
+// Flags: --expose-internals
 
 const common = require('../common');
 const readline = require('readline');
diff --git a/test/parallel/test-repl-history-perm.js b/test/parallel/test-repl-history-perm.js
index 3db2a009eb053b..7297689422eba1 100644
--- a/test/parallel/test-repl-history-perm.js
+++ b/test/parallel/test-repl-history-perm.js
@@ -2,7 +2,7 @@
 
 // Verifies that the REPL history file is created with mode 0600
 
-// Flags: --expose_internals
+// Flags: --expose-internals
 
 const common = require('../common');
 
diff --git a/test/parallel/test-repl.js b/test/parallel/test-repl.js
index a7b0b453e9068c..cb66c22457fdc2 100644
--- a/test/parallel/test-repl.js
+++ b/test/parallel/test-repl.js
@@ -560,7 +560,7 @@ const errorTests = [
     expect: '... ... ... undefined'
   },
   // REPL should get a normal require() function, not one that allows
-  // access to internal modules without the --expose_internals flag.
+  // access to internal modules without the --expose-internals flag.
   {
     send: 'require("internal/repl")',
     expect: [
diff --git a/test/parallel/test-safe-get-env.js b/test/parallel/test-safe-get-env.js
index 0bee9971dbb3eb..f57dcb566d672d 100644
--- a/test/parallel/test-safe-get-env.js
+++ b/test/parallel/test-safe-get-env.js
@@ -1,5 +1,5 @@
 'use strict';
-// Flags: --expose_internals
+// Flags: --expose-internals
 
 require('../common');
 const assert = require('assert');
diff --git a/test/parallel/test-stream-buffer-list.js b/test/parallel/test-stream-buffer-list.js
index c78efeea24bf6b..5b495a41e08545 100644
--- a/test/parallel/test-stream-buffer-list.js
+++ b/test/parallel/test-stream-buffer-list.js
@@ -1,4 +1,4 @@
-// Flags: --expose_internals
+// Flags: --expose-internals
 'use strict';
 require('../common');
 const assert = require('assert');
diff --git a/test/parallel/test-stream2-readable-from-list.js b/test/parallel/test-stream2-readable-from-list.js
index 0ab7c059d66a85..6564a01691f09e 100644
--- a/test/parallel/test-stream2-readable-from-list.js
+++ b/test/parallel/test-stream2-readable-from-list.js
@@ -19,7 +19,7 @@
 // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-// Flags: --expose_internals
+// Flags: --expose-internals
 'use strict';
 require('../common');
 const assert = require('assert');
diff --git a/test/parallel/test-tls-parse-cert-string.js b/test/parallel/test-tls-parse-cert-string.js
index a3062c227e6fd1..f5412cad4074c4 100644
--- a/test/parallel/test-tls-parse-cert-string.js
+++ b/test/parallel/test-tls-parse-cert-string.js
@@ -10,7 +10,7 @@ const {
   restoreStderr
 } = require('../common/hijackstdio');
 const assert = require('assert');
-// Flags: --expose_internals
+// Flags: --expose-internals
 const internalTLS = require('internal/tls');
 const tls = require('tls');
 
diff --git a/test/parallel/test-tls-wrap-timeout.js b/test/parallel/test-tls-wrap-timeout.js
index 6ae2c39c59b8d9..7b9cb4170c888f 100644
--- a/test/parallel/test-tls-wrap-timeout.js
+++ b/test/parallel/test-tls-wrap-timeout.js
@@ -1,4 +1,4 @@
-// Flags: --expose_internals
+// Flags: --expose-internals
 
 'use strict';
 const common = require('../common');
diff --git a/test/parallel/test-util-internal.js b/test/parallel/test-util-internal.js
index f16ccfdbdc534f..cd38f3e7c57f44 100644
--- a/test/parallel/test-util-internal.js
+++ b/test/parallel/test-util-internal.js
@@ -1,5 +1,5 @@
 'use strict';
-// Flags: --expose_internals
+// Flags: --expose-internals
 
 require('../common');
 const assert = require('assert');