A liquid spray tool for an endoscope includes a flexible tube to be inserted into and extracted from a treatment tool insertion channel of the endoscope, a liquid storage pouch configured to pool solution to be conveyed into the flexible tube therein, a liquid measuring pouch for measuring an amount of the solution which is arranged between a rear end of the flexible tube and a distal end of the liquid storage pouch, and a first one-way valve arranged between the liquid storage pouch and the liquid measuring pouch, the first one-way valve being configured to allow the solution to pass theretrough from an inside of the liquid storage pouch to an inside of the liquid measuring pouch, and to prevent the solution from passing theretrough from the inside of the liquid measuring pouch to the inside of the liquid storage pouch.