diff --git a/plugins/node/opentelemetry-instrumentation-pg/src/utils.ts b/plugins/node/opentelemetry-instrumentation-pg/src/utils.ts
index d97f7f9c3e..bcf8e4efb7 100644
--- a/plugins/node/opentelemetry-instrumentation-pg/src/utils.ts
+++ b/plugins/node/opentelemetry-instrumentation-pg/src/utils.ts
@@ -94,6 +94,17 @@ export function getConnectionString(params: PgParsedConnectionParams) {
   return `postgresql://${host}:${port}/${database}`;
 }
 
+function getPort(port: number | undefined): number | undefined {
+  // Port may be NaN as parseInt() is used on the value, passing null will result in NaN being parsed.
+  // https://github.com/brianc/node-postgres/blob/2a8efbee09a284be12748ed3962bc9b816965e36/packages/pg/lib/connection-parameters.js#L66
+  if (Number.isInteger(port)) {
+    return port;
+  }
+
+  // Unable to find the default used in pg code, so falling back to 'undefined'.
+  return undefined;
+}
+
 export function getSemanticAttributesFromConnection(
   params: PgParsedConnectionParams
 ) {
@@ -101,7 +112,7 @@ export function getSemanticAttributesFromConnection(
     [SemanticAttributes.DB_NAME]: params.database, // required
     [SemanticAttributes.DB_CONNECTION_STRING]: getConnectionString(params), // required
     [SemanticAttributes.NET_PEER_NAME]: params.host, // required
-    [SemanticAttributes.NET_PEER_PORT]: params.port,
+    [SemanticAttributes.NET_PEER_PORT]: getPort(params.port),
     [SemanticAttributes.DB_USER]: params.user,
   };
 }
diff --git a/plugins/node/opentelemetry-instrumentation-pg/test/utils.test.ts b/plugins/node/opentelemetry-instrumentation-pg/test/utils.test.ts
index ec32b55694..d3dca9aa3c 100644
--- a/plugins/node/opentelemetry-instrumentation-pg/test/utils.test.ts
+++ b/plugins/node/opentelemetry-instrumentation-pg/test/utils.test.ts
@@ -28,6 +28,7 @@ import { PgInstrumentationConfig } from '../src';
 import { AttributeNames } from '../src/enums/AttributeNames';
 import { PgClientExtended } from '../src/internal-types';
 import * as utils from '../src/utils';
+import { SemanticAttributes } from '@opentelemetry/semantic-conventions';
 
 const memoryExporter = new InMemorySpanExporter();
 
@@ -193,4 +194,48 @@ describe('utils.ts', () => {
       assert.deepStrictEqual(pgValues, ['0']);
     });
   });
+
+  describe('.getSemanticAttributesFromConnection()', () => {
+    it('should set port attribute to undefined when port is not an integer', () => {
+      assert.strictEqual(
+        utils.getSemanticAttributesFromConnection({
+          port: Infinity,
+        })[SemanticAttributes.NET_PEER_PORT],
+        undefined
+      );
+      assert.strictEqual(
+        utils.getSemanticAttributesFromConnection({
+          port: -Infinity,
+        })[SemanticAttributes.NET_PEER_PORT],
+        undefined
+      );
+      assert.strictEqual(
+        utils.getSemanticAttributesFromConnection({
+          port: NaN,
+        })[SemanticAttributes.NET_PEER_PORT],
+        undefined
+      );
+      assert.strictEqual(
+        utils.getSemanticAttributesFromConnection({
+          port: 1.234,
+        })[SemanticAttributes.NET_PEER_PORT],
+        undefined
+      );
+    });
+
+    it('should set port attribute when port is an integer', () => {
+      assert.strictEqual(
+        utils.getSemanticAttributesFromConnection({
+          port: 1234,
+        })[SemanticAttributes.NET_PEER_PORT],
+        1234
+      );
+      assert.strictEqual(
+        utils.getSemanticAttributesFromConnection({
+          port: Number.MAX_VALUE,
+        })[SemanticAttributes.NET_PEER_PORT],
+        Number.MAX_VALUE
+      );
+    });
+  });
 });