PURPOSE: A constant field permeability test method with electronic flowmeter and auto level instrument is provided to minimize the error of test by conveniently maintaining a constant level. CONSTITUTION: A constant field permeability test method with electronic flowmeter and auto level instrument as follows. A bore hole is punched on the ground to be tested. A casing(70) is installed to the underground water level(80) vicinity in the bore hole. A tester in which an auto level instrument(30) and a water pipe(50) are installed is place in the casing. A drain valve(40) is opened to start supplying water to the level(60) to be kept constant. An electronic flowmeter(10) is operated and starts testing. If the water level falls below the constant level, the auto level instrument goes down along the water level. If the auto level instrument reaches a predetermined water level, an auto water feeder(20) stops supplying water.
