Most dogs drool, but some dogs drool more than others. Dogs with low-hanging jowls -- such as bulldogs, mastiffs and basset hounds -- can produce copious amounts of slobber. Wet drool is easy to remove from painted walls. Dry drool requires a bit more effort.
Wipe dog drool that is still wet with a moistened paper towel or sponge.
Spray dried drool with a household window cleaner containing trisodium phosphate. It won't harm the paint.
Wipe the cleaner and dried drool with a sponge or paper towel, using a circular motion. The dried drool will lift right off.