Conductor wellhead running tool is the only operating practice to transfer or to run in/out the conductor pipe on platform deck, and it is a key factor on deepwater conductor running. But the related technologies were monopolized by several monopolistic companies abroad. In this paper, one kind of novel locking and releasing mechanical configuration was presented by studying running tool structure, operating principle, operating procedure, as well as operating behavior on semi-submerged platform, job procedure and technical problems on running.It was constructed with T-shaped-round-tip thrusting rod, pyramidal axle sleeve, and circlip. The locking and releasing mechanical structure equipped with guiding mechanism would qualified the running tool to apply in deepwater harsh operating conditions. The stability, the credibility, and the safety of the running tool were conducted by the study on bearing characteristics, operating simulation and finite element simulation on different operating status. The simulation results show that the safety factor of allowable stress is respectively 3.87 and 4.98 under the condition of transferring working procedure and running-in working procedure. By this way, the high cost of deepwater drilling caused by foreign technological embargo in China could be reduced.