The HT-6M is a medium-sized tokamak being built in China. The principal aim of the project is to study high-power auxiliary heating (1-MW neutral beam injection, 1-MW ion cyclotron resonance heating, and 100-kW electron cyclotron resonance heating), high-β experiments, the transport process, and the formation and diffusion process of impurities. The main device parameters are: major plasma radius R = 65 cm, minor plasma radius a = 20 cm, plasma current Ip = 150 kA, discharge time τ = 750 ms, toroidal field Bt = 15 kG. Simplicity of construction, accessibility to the plasma, reliability in operation, and convenience f or maintenance were particularly emphasized in the design. The important design features of the device and power supply system are described.