Abstract: The Sino United Spherical Tokamak (SUNIST), built in 2002, is the first Tokamak device with a low aspect ratio (R/a≈1. 3). It has a structure of viton cross sealing and electrical insulation. The nominal parameters are as follows: major R = 30 cm, minor radius a= 23 cm, natural elongation κ≈1. 6, aspect ratio R/a≈1. 3, on-axis toroidal field BT = 0. 15 T and plasma current IP = 50 kA. Reproducible discharge with plasma current of 52 kA has been achieved in initial ohmic heating experiments.