The laboratory developed and installed a 210 MPa high-pressure gas seal system and a 15 MPa high-pressure chamber and built test pools in the size of 25m×15m×10m and 6m×6m×6m (length× width× depth) to simulate the working environment for subsea equipment. The lab also installed a ROV subsea robot observation system to observe the test process in real time and identify the leak point and leak source. By doing so, the lab had successful research and implementation of air tightness test and detection at a water depth of 1,000 meters.