This paper compared the transient performance of Synchronous Condenser and Static Compensator (STATCOM) at HVDC systems. The impacts of the two reactive power compensators to the connected HVDC system during various aspects of transients, including fault recovery, temporary over voltage and commutation failure, are investigated based on Electromagnetic Transients (EMT) Simulation. The study results demonstrated that STATCOMs and SCs have the similar performance during those transients.