diff --git a/esphome/components/binary_sensor/__init__.py b/esphome/components/binary_sensor/__init__.py
index d66b79a2d2..c4de2023ca 100644
--- a/esphome/components/binary_sensor/__init__.py
+++ b/esphome/components/binary_sensor/__init__.py
@@ -30,6 +30,7 @@ from esphome.const import (
     DEVICE_CLASS_EMPTY,
     DEVICE_CLASS_BATTERY,
     DEVICE_CLASS_BATTERY_CHARGING,
+    DEVICE_CLASS_CARBON_MONOXIDE,
     DEVICE_CLASS_COLD,
     DEVICE_CLASS_CONNECTIVITY,
     DEVICE_CLASS_DOOR,
@@ -64,6 +65,7 @@ DEVICE_CLASSES = [
     DEVICE_CLASS_EMPTY,
     DEVICE_CLASS_BATTERY,
     DEVICE_CLASS_BATTERY_CHARGING,
+    DEVICE_CLASS_CARBON_MONOXIDE,
     DEVICE_CLASS_COLD,
     DEVICE_CLASS_CONNECTIVITY,
     DEVICE_CLASS_DOOR,