diff --git a/lib/crypto.js b/lib/crypto.js
index 77debb9471f..35d54b5efb3 100644
--- a/lib/crypto.js
+++ b/lib/crypto.js
@@ -37,6 +37,7 @@ assertCrypto();
 
 const {
   ERR_CRYPTO_FIPS_FORCED,
+  ERR_WORKER_UNSUPPORTED_OPERATION,
 } = require('internal/errors').codes;
 const constants = internalBinding('constants').crypto;
 const { getOptionValue } = require('internal/options');
@@ -127,6 +128,12 @@ function lazyWebCrypto() {
   return webcrypto;
 }
 
+let ownsProcessState;
+function lazyOwnsProcessState() {
+  ownsProcessState ??= require('internal/worker').ownsProcessState;
+  return ownsProcessState;
+}
+
 // These helper functions are needed because the constructors can
 // use new, in which case V8 cannot inline the recursive constructor call
 function createHash(algorithm, options) {
@@ -250,6 +257,9 @@ function setFips(val) {
     if (val) return;
     throw new ERR_CRYPTO_FIPS_FORCED();
   } else {
+    if (!lazyOwnsProcessState()) {
+      throw new ERR_WORKER_UNSUPPORTED_OPERATION('Calling crypto.setFips()');
+    }
     setFipsCrypto(val);
   }
 }
diff --git a/src/crypto/crypto_util.cc b/src/crypto/crypto_util.cc
index 5d8f0bbe8e3..7da959b45d4 100644
--- a/src/crypto/crypto_util.cc
+++ b/src/crypto/crypto_util.cc
@@ -218,8 +218,7 @@ void SetFipsCrypto(const FunctionCallbackInfo<Value>& args) {
 
   CHECK(!per_process::cli_options->force_fips_crypto);
   Environment* env = Environment::GetCurrent(args);
-  // TODO(addaleax): This should not be possible to set from worker threads.
-  // CHECK(env->owns_process_state());
+  CHECK(env->owns_process_state());
   bool enable = args[0]->BooleanValue(env->isolate());
 
 #if OPENSSL_VERSION_MAJOR >= 3
diff --git a/test/parallel/test-crypto-fips.js b/test/parallel/test-crypto-fips.js
index cc3e4eed79d..964d5dbb405 100644
--- a/test/parallel/test-crypto-fips.js
+++ b/test/parallel/test-crypto-fips.js
@@ -85,6 +85,14 @@ testHelper(
   'require("crypto").getFips()',
   { ...process.env, 'OPENSSL_CONF': ' ' });
 
+// Toggling fips with setFips should not be allowed from a worker thread
+testHelper(
+  'stderr',
+  [],
+  'Calling crypto.setFips() is not supported in workers',
+  'new worker_threads.Worker(\'require("crypto").setFips(true);\', { eval: true })',
+  process.env);
+
 // This should succeed for both FIPS and non-FIPS builds in combination with
 // OpenSSL 1.1.1 or OpenSSL 3.0
 const test_result = testFipsCrypto();