Abstract: In order to solve the problems of using the equipment of water injection leakage in the upward slant hole to determining the height of water flowing fractured zone, the change-over device had been invented. It could connect and switch between the water-injection system and the capsules or the test section by moving the drill pipe up or down. The equipment was improved with the change-over device. It had simplified the orifice meter and the water supply system, and eliminated the hidden trouble of plugging due to the water or gas injection pipe line using for swelling the capsule with a large amount of water and some water pressure in the deep hole. The results showed that the improved equipment was used in the first mining face of Gaojiabu Coal Mine, and the heights of water flowing fractured zone of TD1, TD2, and TD3 drillings were 86.56 、84.37 and 88.03 m respectively. The improved equipment had a simple structure, high reliability, and wide applicability, and could be used to determining the height of water flowing fractured zone in the upward slant hole.