diff --git a/cmd/flux/diff_kustomization_test.go b/cmd/flux/diff_kustomization_test.go
index 69577dd0..46ef2b44 100644
--- a/cmd/flux/diff_kustomization_test.go
+++ b/cmd/flux/diff_kustomization_test.go
@@ -270,3 +270,36 @@ func createObjectFromFile(objectFile string, templateValues map[string]string, t
 
 	return clientObjects
 }
+
+// TestDiffKustomizationDriftIgnoreRules tests `flux diff ks` with drift ignore
+// rules. A service with a drifted port is pre-applied to the cluster, and the
+// kustomization specifies driftIgnoreRules that ignore /spec/ports on Services.
+// The diff should not show the service as drifted.
+func TestDiffKustomizationDriftIgnoreRules(t *testing.T) {
+	tmpl := map[string]string{
+		"fluxns": allocateNamespace("flux-system"),
+	}
+	setupTestNamespace(tmpl["fluxns"], t)
+
+	b, _ := build.NewBuilder("podinfo", "", build.WithClientConfig(kubeconfigArgs, kubeclientOptions))
+	resourceManager, err := b.Manager()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Pre-apply the drifted service (port 9899 instead of 9898) without Flux labels.
+	if _, err := resourceManager.ApplyAll(context.Background(), createObjectFromFile("./testdata/diff-kustomization/drifted-service-no-labels.yaml", tmpl, t), ssa.DefaultApplyOptions()); err != nil {
+		t.Fatal(err)
+	}
+
+	cmd := cmdTestCase{
+		args: "diff kustomization podinfo --path ./testdata/build-kustomization/podinfo --progress-bar=false " +
+			"--kustomization-file ./testdata/diff-kustomization/flux-kustomization-drift-ignore.yaml " +
+			"--ignore-not-found" +
+			" -n " + tmpl["fluxns"],
+		assert: assertGoldenFile("./testdata/diff-kustomization/diff-with-drift-ignore.golden"),
+	}
+	cmd.runTestCmd(t)
+
+	testEnv.DeleteObjectFile("./testdata/diff-kustomization/drifted-service-no-labels.yaml", tmpl, t)
+}
diff --git a/cmd/flux/testdata/diff-kustomization/diff-with-drift-ignore.golden b/cmd/flux/testdata/diff-kustomization/diff-with-drift-ignore.golden
new file mode 100644
index 00000000..67b137de
--- /dev/null
+++ b/cmd/flux/testdata/diff-kustomization/diff-with-drift-ignore.golden
@@ -0,0 +1,14 @@
+► Deployment/default/podinfo created
+► HorizontalPodAutoscaler/default/podinfo created
+► Service/default/podinfo drifted
+
+metadata
++ one map entry added:
+  labels:
+    kustomize.toolkit.fluxcd.io/name: podinfo
+    kustomize.toolkit.fluxcd.io/namespace:
+
+► Secret/default/docker-secret created
+► Secret/default/secret-basic-auth-stringdata created
+► Secret/default/podinfo-token-77t89m9b67 created
+► Secret/default/db-user-pass-bkbd782d2c created
diff --git a/cmd/flux/testdata/diff-kustomization/drifted-service-no-labels.yaml b/cmd/flux/testdata/diff-kustomization/drifted-service-no-labels.yaml
new file mode 100644
index 00000000..539a99db
--- /dev/null
+++ b/cmd/flux/testdata/diff-kustomization/drifted-service-no-labels.yaml
@@ -0,0 +1,18 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: podinfo
+  namespace: default
+spec:
+  type: ClusterIP
+  selector:
+    app: podinfo
+  ports:
+    - name: http
+      port: 9899
+      protocol: TCP
+      targetPort: http
+    - port: 9999
+      targetPort: grpc
+      protocol: TCP
+      name: grpc
diff --git a/cmd/flux/testdata/diff-kustomization/flux-kustomization-drift-ignore.yaml b/cmd/flux/testdata/diff-kustomization/flux-kustomization-drift-ignore.yaml
new file mode 100644
index 00000000..157b56b5
--- /dev/null
+++ b/cmd/flux/testdata/diff-kustomization/flux-kustomization-drift-ignore.yaml
@@ -0,0 +1,19 @@
+---
+apiVersion: kustomize.toolkit.fluxcd.io/v1
+kind: Kustomization
+metadata:
+  name: podinfo
+spec:
+  interval: 5m0s
+  path: ./kustomize
+  force: true
+  prune: true
+  sourceRef:
+    kind: GitRepository
+    name: podinfo
+  targetNamespace: default
+  ignore:
+    - paths:
+        - "/spec/ports"
+      target:
+        kind: Service
diff --git a/internal/build/diff.go b/internal/build/diff.go
index 72063d9f..ce6800ed 100644
--- a/internal/build/diff.go
+++ b/internal/build/diff.go
@@ -41,6 +41,7 @@ import (
 	"github.com/fluxcd/cli-utils/pkg/object"
 	kustomizev1 "github.com/fluxcd/kustomize-controller/api/v1"
 	"github.com/fluxcd/pkg/ssa"
+	"github.com/fluxcd/pkg/ssa/jsondiff"
 	"github.com/fluxcd/pkg/ssa/normalize"
 	ssautil "github.com/fluxcd/pkg/ssa/utils"
 
@@ -94,6 +95,28 @@ func (b *Builder) diff() (string, bool, error) {
 	ctx, cancel := context.WithTimeout(context.Background(), b.timeout)
 	defer cancel()
 
+	// Convert drift ignore rules from the Kustomization spec to jsondiff.IgnoreRule.
+	var driftIgnoreRules []jsondiff.IgnoreRule
+	if rules := b.kustomization.Spec.Ignore; len(rules) > 0 {
+		driftIgnoreRules = make([]jsondiff.IgnoreRule, len(rules))
+		for i, rule := range rules {
+			driftIgnoreRules[i] = jsondiff.IgnoreRule{
+				Paths: rule.Paths,
+			}
+			if rule.Target != nil {
+				driftIgnoreRules[i].Selector = &jsondiff.Selector{
+					Group:              rule.Target.Group,
+					Version:            rule.Target.Version,
+					Kind:               rule.Target.Kind,
+					Name:               rule.Target.Name,
+					Namespace:          rule.Target.Namespace,
+					AnnotationSelector: rule.Target.AnnotationSelector,
+					LabelSelector:      rule.Target.LabelSelector,
+				}
+			}
+		}
+	}
+
 	var diffErrs []error
 	// create an inventory of objects to be reconciled
 	newInventory := newInventory()
@@ -109,6 +132,7 @@ func (b *Builder) diff() (string, bool, error) {
 			ForceSelector: map[string]string{
 				"kustomize.toolkit.fluxcd.io/force": "enabled",
 			},
+			DriftIgnoreRules: driftIgnoreRules,
 		}
 		change, liveObject, mergedObject, err := resourceManager.Diff(ctx, obj, diffOptions)
 		if err != nil {