The occurrence of well leakage in drilling engineering not only seriously affects safe， fast， and low-cost drilling， but also seriously pollutes the ore layer and affects its production. The research on methods and instruments for determining the location of leakage layers is of great significance for drilling production under complex geological conditions. This article elaborates on the composition， parameter acquisition process， processing principle， mechanical structure， and testing situation of the developed CLY-1 multi-parameter intelligent leak detector. The lower probe tube of the multi-parameter intelligent leak detection system is directly connected to the lower end of the drill pipe or steel wire rope and placed into the hole for testing. The inner probe tube in the hole performs numerical testing on four parameters such as mud flow rate， well temperature， well pressure， and natural gamma along the depth of the hole， and stores the collected data in a certain format in the memory. After the probe is removed from the well， it is connected to the ground computer system to store the collected data in memory to form a digital document， providing relevant personnel with the basis for identifying leakage and surge layers.