diff --git a/cmd/cosign/cli/signblob.go b/cmd/cosign/cli/signblob.go
index b09d6ee3b31..50a89f6b076 100644
--- a/cmd/cosign/cli/signblob.go
+++ b/cmd/cosign/cli/signblob.go
@@ -41,6 +41,9 @@ func SignBlob() *cobra.Command {
   # sign a blob with a local key pair file
   cosign sign-blob --key cosign.key <FILE>
 
+  # sign a blob with a key stored in an environment variable
+  cosign sign-blob --key env://[ENV_VAR] <FILE>
+
   # sign a blob with a key pair stored in Azure Key Vault
   cosign sign-blob --key azurekms://[VAULT_NAME][VAULT_URI]/[KEY] <FILE>
 
diff --git a/doc/cosign_sign-blob.md b/doc/cosign_sign-blob.md
index d512d6b6276..d58f0367985 100644
--- a/doc/cosign_sign-blob.md
+++ b/doc/cosign_sign-blob.md
@@ -17,6 +17,9 @@ cosign sign-blob [flags]
   # sign a blob with a local key pair file
   cosign sign-blob --key cosign.key <FILE>
 
+  # sign a blob with a key stored in an environment variable
+  cosign sign-blob --key env://[ENV_VAR] <FILE>
+
   # sign a blob with a key pair stored in Azure Key Vault
   cosign sign-blob --key azurekms://[VAULT_NAME][VAULT_URI]/[KEY] <FILE>