[en] Steady Control Rod Drive Mechanism (CRDM) in Xi'an Pulsed Reactor is the key equipment to implement start-up, shutdown reactor and adjust power of reactor. It takes ball screws as drive machine, engaged electromagnet to drive steady control rod up and down, disengaged electromagnet to drop the control rod rapidly. The structure characteristics, the parameter of design and the test results of CRDM are presented. The machine has been used for Xi'an Pulse Reactor successfully