Yes, it is safe to leave your Christmas tree lights on. However, it's important to follow some safety precautions. Make sure to turn off the lights when you're not home or before you go to bed. Also, make sure the lights are not near any flammable materials such as curtains or other decorations. Additionally, it's important to check your lights regularly for any signs of damage or wear and tear. If you notice any issues with the lights, it's best to replace them immediately. Following these simple steps can help ensure a safe and enjoyable holiday season.