PROBLEM TO BE SOLVED: To provide an endoscope washing/disinfection device which is, after finishing to pour the last solution of a drug solution bottle therein, capable of stopping filling the medical solution tank with the drug solution.SOLUTION: The endoscope washing/disinfection device includes: a drug solution tank 100 for storing a drug solution poured from a bottle a solenoid valve 102 for cutting off a passage for pouring the drug solution into the tank 100 a first determination part (a control part 120, a first sensor 114, and the like) for determining that an introduction amount of the drug solution to be stored in the tank 100 reaches a prescribed amount and the control part 120 that, after the introduction amount of the drug solution reaches the prescribed amount, compares a first distance from a reference point to a liquid level of the drug solution at a first time, with a second distance from the reference point to a liquid level of the drug solution at a second time on the basis of a liquid level position detection by a second sensor 111, and, when determining that a variation value of the liquid level of the drug solution is within a prescribed range, cuts off the passage through which the drug solution is poured from the bottle to the tank.
