Abstract: The helium circulator is a key component for the 10MW High Temperature Gas-cooled Reactor （HTR-10）. The circulator operates at 250℃, 3.0MPa helium condition in order to transport the core heat to the steam generator. The design of the helium circulator involves the overall construction, the impeller type, the cooling system, the bearings, the instrumentation, the electrical penetrations, and the shutoff valve. Ex-factory test and cold and hot tests after the installation have been carried out for the helium circulator. According to the commissioning requirement of the reactor, initiative operation has been made for the helium circulator. The test and operation results show that the helium circulator meets the requirement of design and operation for HTR-10.