The invention relates to an experiment device for detecting the sealing performance of swelling capsule and sealing liquid, comprising a steel pipe. One end of the steel pipe is plugged by a seal plug, and the other end of the steel pipe is opened; the seal plug is communicated with a foaming liquid container via a high-pressure delivery pipe, and the foaming liquid container is communicated witha high-pressure air resource via the other high-pressure delivery pipe; the two high-pressure delivery pipes are respectively provided with a stop valve; the swelling capsule is arranged in the open end of the steel pipe and is communicated to a hydraulic pump via one high-pressure delivery pipe; at least one steel wire is arranged between the swelling capsule and the steel pipe; and the steel pipe arranged between the swelling capsule and the seal plug is provided with a liquid feed port and is simultaneously provided with a sealed cap for the liquid feed port. The invention utilizes one section of steel pipe, one swelling capsule, the sealing liquid and the steel wire to simulate pressure measurement and drilling. One device can simultaneously detect the sealing performance of two mediaof the sealing liquid and the swelling capsule. The invention has the advantages of simple operation and accurate measuring result.