The present invention relates to an experimental device and experimental method for the mechanical performance of a marine test pipe string. The experimental device comprises a computer, a limiting stopper, a cylindrical track, a track seat, a bolt, a power wheel, an inner tube, a fixed connector, a driven wheel, a wall climbing vehicle frame, a strain gauge, a pool, a gas storage tank, a regulating valve, a flow meter, a gas pipeline, an outer pipe, and a cable. Before conducting the experiment, a suitable pool is found; the pool must have a certain depth and size, and the entire experimentaldevice can be arranged in the pool; a track is installed on the pool wall on one side of the pool, a wall climbing vehicle runs on the track, and a test pipe string is installed on the wall climbingvehicle through a special connector; during the experiment, the regulating valve is opened for ventilation, and the wall climbing vehicle is driven to carry the test pipe string to move in the water;and the disturbance of the water flow and the flow of the high-pressure gas cause the test pipe string to vibrate and buckle, the strain gauge is configured to collect data and transmit the data fromthe cable to the computer, and the mechanical performance characteristics of the inner pipe of the test pipe string in the marine environment are obtained. The experimental device provided by the present invention has the advantages of safety and reliability, a simple operation, and accuracy in data measurement.