diff --git a/codegen/config.go b/codegen/config.go
index 01eb87cad0..275e3d4dfb 100644
--- a/codegen/config.go
+++ b/codegen/config.go
@@ -46,7 +46,7 @@ func LoadConfig(filename string) (*Config, error) {
 		return nil, errors.Wrap(err, "unable to read config")
 	}
 
-	if err := yaml.Unmarshal(b, &config); err != nil {
+	if err := yaml.UnmarshalStrict(b, &config); err != nil {
 		return nil, errors.Wrap(err, "unable to parse config")
 	}
 
diff --git a/codegen/config_test.go b/codegen/config_test.go
index 34aebeb168..e4161d9c31 100644
--- a/codegen/config_test.go
+++ b/codegen/config_test.go
@@ -20,6 +20,11 @@ func TestLoadConfig(t *testing.T) {
 		_, err := LoadConfig("testdata/cfg/malformedconfig.yml")
 		require.EqualError(t, err, "unable to parse config: yaml: unmarshal errors:\n  line 1: cannot unmarshal !!str `asdf` into codegen.Config")
 	})
+
+	t.Run("unknown keys", func(t *testing.T) {
+		_, err := LoadConfig("testdata/cfg/unknownkeys.yml")
+		require.EqualError(t, err, "unable to parse config: yaml: unmarshal errors:\n  line 2: field unknown not found in type codegen.Config")
+	})
 }
 
 func TestLoadDefaultConfig(t *testing.T) {
diff --git a/codegen/testdata/cfg/unknownkeys.yml b/codegen/testdata/cfg/unknownkeys.yml
new file mode 100644
index 0000000000..dbf095fd01
--- /dev/null
+++ b/codegen/testdata/cfg/unknownkeys.yml
@@ -0,0 +1,2 @@
+schema: outer
+unknown: foo