Development of a superconducting undulator prototype is ongoing at the SSRF. The 50-period superconducting magnet of this prototype is based on NbTi/Cu conductors. The period length is 16 mm. The magnetic gap is 9.5 mm and the vacuum gap is 7.5 mm. The peak value of the magnetic fields on beam axis is 0.67 T with the operation current of 400 A. Cooling system includes 4 cryocoolers and independent cooling circuits for magnet and the beam vacuum chamber. In this report we present the main parameters, components, and the R&D process of this prototype. Methods and results of the stand-alone test are also included in detail.