The present invention provides a balloon controller for an endoscope apparatus having a fluid supply and drawing device which communicates with at least one of a balloon attached to an insertion portion of an endoscope and a balloon attached to an insertion assist implement for guiding the insertion portion when the insertion portion is inserted, and which supplies a fluid to each balloon or draws the fluid from the balloon, the balloon controller comprising: a leakage device provided in tube paths for communication between the balloons and the fluid supply and drawing device, the leakage device being capable of leaking the fluid.