There are provided an endoscope, an endoscope system, a method of determining the leakage of an endoscope, and a non-transitory computer readable recording medium storing a leakage determination program for an endoscope that can detect the occurrence of leakage with high accuracy. An endoscope includes an enclosed space, a pressure sensor that detects pressure inside the enclosed space, and a storage unit that stores reference pressure, which is detected by the pressure sensor at a first timing in a state where pressure is applied to the enclosed space with respect to the atmospheric pressure by a pump, in association with detection time information. The leakage of the enclosed space is determined on the basis of pressure that is detected by the pressure sensor at a second timing after the first timing, detection time information about the pressure, the reference pressure, and the detection time information.
