diff --git a/pkg/reconciler/pipelinerun/pipelinerun.go b/pkg/reconciler/pipelinerun/pipelinerun.go
index 899ab6346dc..5412cbfd77c 100644
--- a/pkg/reconciler/pipelinerun/pipelinerun.go
+++ b/pkg/reconciler/pipelinerun/pipelinerun.go
@@ -84,8 +84,9 @@ const (
 	// ReasonInvalidWorkspaceBinding indicates that a Pipeline expects a workspace but a
 	// PipelineRun has provided an invalid binding.
 	ReasonInvalidWorkspaceBinding = "InvalidWorkspaceBindings"
-	// ReasonInvalidServiceAccountMapping indicates that PipelineRun.Spec.TaskRunSpecs[].TaskServiceAccountName is defined with a wrong taskName
-	ReasonInvalidServiceAccountMapping = "InvalidServiceAccountMappings"
+	// ReasonInvalidTaskRunSpec indicates that PipelineRun.Spec.TaskRunSpecs[].PipelineTaskName is defined with
+	// a not exist taskName in pipelineSpec.
+	ReasonInvalidTaskRunSpec = "InvalidTaskRunSpecs"
 	// ReasonParameterTypeMismatch indicates that the reason for the failure status is that
 	// parameter(s) declared in the PipelineRun do not have the some declared type as the
 	// parameters(s) declared in the Pipeline that they are supposed to override.
@@ -512,7 +513,7 @@ func (c *Reconciler) reconcile(ctx context.Context, pr *v1.PipelineRun, getPipel
 
 	// Ensure that the TaskRunSpecs defined are correct.
 	if err := resources.ValidateTaskRunSpecs(pipelineSpec, pr); err != nil {
-		pr.Status.MarkFailed(ReasonInvalidServiceAccountMapping,
+		pr.Status.MarkFailed(ReasonInvalidTaskRunSpec,
 			"PipelineRun %s/%s doesn't define taskRunSpecs correctly: %s",
 			pr.Namespace, pr.Name, err)
 		return controller.NewPermanentError(err)
diff --git a/pkg/reconciler/pipelinerun/pipelinerun_test.go b/pkg/reconciler/pipelinerun/pipelinerun_test.go
index 512ac93d33f..d02bb8264d3 100644
--- a/pkg/reconciler/pipelinerun/pipelinerun_test.go
+++ b/pkg/reconciler/pipelinerun/pipelinerun_test.go
@@ -7049,6 +7049,24 @@ spec:
         params:
           - name: platform
             value: linux
+`),
+		parse.MustParseV1PipelineRun(t, `
+metadata:
+  name: pipelinerun-with-invalid-taskrunspecs
+  namespace: foo
+spec:
+  taskRunSpecs:
+  - metadata:
+      annotations:
+        env: test
+    pipelineTaskName: invalid-task-name
+  pipelineSpec:
+    tasks:
+    - name: pt0
+      taskSpec:
+        steps:
+        - image: foo:latest
+  serviceAccountName: test-sa
 `),
 	}
 
@@ -7080,6 +7098,9 @@ spec:
 		}, {
 			name:   "pipelinerun-matrix-param-invalid-type",
 			reason: ReasonInvalidMatrixParameterTypes,
+		}, {
+			name:   "pipelinerun-with-invalid-taskrunspecs",
+			reason: ReasonInvalidTaskRunSpec,
 		},
 	}
 	for _, tc := range testCases {