If it's the spray that was common in the 70's, yeah...you can paint over it. However, it isn't that hard to remove it and get rid of the nasty, dirt and cob web catching mess. You just mist it with water, let sit a few minutes, and it will scrap off the ceiling like butter if you use a trowel. Sure, it's messy, but it's not hard to do. We had our bedroom ceiling cleaned off and primed in one day.