diff --git a/pkg/helmexec/exec.go b/pkg/helmexec/exec.go
index 209949ec..0fa711d8 100644
--- a/pkg/helmexec/exec.go
+++ b/pkg/helmexec/exec.go
@@ -446,6 +446,11 @@ func (helm *execer) DiffRelease(context HelmContext, name, chart string, suppres
 		enableLiveOutput := false
 		overrideEnableLiveOutput = &enableLiveOutput
 	}
+
+	if helm.IsHelm3() && helm.postRenderer != "" {
+		flags = append(flags, "--post-renderer", helm.postRenderer)
+	}
+
 	out, err := helm.exec(append(append(preArgs, "diff", "upgrade", "--allow-unreleased", name, chart), flags...), env, overrideEnableLiveOutput)
 	// Do our best to write STDOUT only when diff existed
 	// Unfortunately, this works only when you run helmfile with `--detailed-exitcode`
diff --git a/pkg/state/state.go b/pkg/state/state.go
index 5d4bca7b..d5943997 100644
--- a/pkg/state/state.go
+++ b/pkg/state/state.go
@@ -2605,6 +2605,14 @@ func (st *HelmState) flagsForDiff(helm helmexec.Interface, release *ReleaseSpec,
 		return nil, nil, err
 	}
 
+	if helm.IsHelm3() && helm.GetPostRenderer() == "" {
+		if release.PostRenderer != nil && *release.PostRenderer != "" {
+			flags = append(flags, "--post-renderer", *release.PostRenderer)
+		} else if st.HelmDefaults.PostRenderer != nil && *st.HelmDefaults.PostRenderer != "" {
+			flags = append(flags, "--post-renderer", *st.HelmDefaults.PostRenderer)
+		}
+	}
+
 	common, files, err := st.namespaceAndValuesFlags(helm, release, workerIndex)
 	if err != nil {
 		return nil, files, err