diff --git a/.changelog/3225.txt b/.changelog/3225.txt
new file mode 100644
index 0000000000..ba968e8182
--- /dev/null
+++ b/.changelog/3225.txt
@@ -0,0 +1,3 @@
+```release-note:bug
+compute: fixed bug where `google_compute_instance.scheduling.node_affinities.operator` would incorrectly accept `NOT` rather than `NOT_IN`.
+```
diff --git a/google-beta/compute_instance_helpers.go b/google-beta/compute_instance_helpers.go
index ba9ab707e5..f1cfc93480 100644
--- a/google-beta/compute_instance_helpers.go
+++ b/google-beta/compute_instance_helpers.go
@@ -22,7 +22,7 @@ func instanceSchedulingNodeAffinitiesElemSchema() *schema.Resource {
 				Type:         schema.TypeString,
 				Required:     true,
 				ForceNew:     true,
-				ValidateFunc: validation.StringInSlice([]string{"IN", "NOT"}, false),
+				ValidateFunc: validation.StringInSlice([]string{"IN", "NOT_IN"}, false),
 			},
 			"values": {
 				Type:     schema.TypeSet,
diff --git a/google-beta/resource_compute_instance_test.go b/google-beta/resource_compute_instance_test.go
index e6d4eb4e2b..3e728d5112 100644
--- a/google-beta/resource_compute_instance_test.go
+++ b/google-beta/resource_compute_instance_test.go
@@ -4240,6 +4240,12 @@ resource "google_compute_instance" "foobar" {
       values   = ["test"]
     }
 
+    node_affinities {
+      key      = "tfacc"
+      operator = "NOT_IN"
+      values   = ["not_here"]
+    }
+
     node_affinities {
       key      = "compute.googleapis.com/node-group-name"
       operator = "IN"
@@ -4302,6 +4308,12 @@ resource "google_compute_instance" "foobar" {
       values   = ["test", "updatedlabel"]
     }
 
+    node_affinities {
+      key      = "tfacc"
+      operator = "NOT_IN"
+      values   = ["not_here"]
+    }
+
     node_affinities {
       key      = "compute.googleapis.com/node-group-name"
       operator = "IN"
diff --git a/website/docs/r/compute_instance.html.markdown b/website/docs/r/compute_instance.html.markdown
index 4337d858fd..093d4cd5f9 100644
--- a/website/docs/r/compute_instance.html.markdown
+++ b/website/docs/r/compute_instance.html.markdown
@@ -333,7 +333,7 @@ The `node_affinities` block supports:
 * `key` (Required) - The key for the node affinity label.
 
 * `operator` (Required) - The operator. Can be `IN` for node-affinities
-    or `NOT` for anti-affinities.
+    or `NOT_IN` for anti-affinities.
 
 * `value` (Required) - The values for the node affinity label.
 
diff --git a/website/docs/r/compute_instance_template.html.markdown b/website/docs/r/compute_instance_template.html.markdown
index d6318fad75..f304967080 100644
--- a/website/docs/r/compute_instance_template.html.markdown
+++ b/website/docs/r/compute_instance_template.html.markdown
@@ -394,7 +394,7 @@ The `node_affinities` block supports:
 * `key` (Required) - The key for the node affinity label.
 
 * `operator` (Required) - The operator. Can be `IN` for node-affinities
-    or `NOT` for anti-affinities.
+    or `NOT_IN` for anti-affinities.
 
 * `value` (Required) - The values for the node affinity label.