This experiment was aimed to improve the flexibility and smoothness of the jet polishing experiment platform used for completing polishing process of small-sized objcets. The S curve acceleration and deceleration algorithm for seven-segment was applied to the platform control system. Matlab simulation results and experiment results for T-curve and S-curve Acc/Dcc control algorithms based on RT-LINUX CNC system was compared and analyzed to verify the performance of the algorithm. Compared with the T-curve control algorithm, the S-curve control algorithm could make the velocity shift smoothly with small error, although the processing took longer time. It showed that the S curve acceleration and deceleration control method used in the jet polishing test platform can make the speed more smooth, and improve the stability and flexible machining performance.