In order to solve the shortcomings of software interpolation such as slow speed, poor portability, this paper has used hardware to implement the interpolation function in Computer Numerical Control (CNC) system. With VHSIC Hardware Description Language (VHDL) in Quartus II 9.0 development environment, based on FPGA of Altera company CYCLONE II series, several interpolation algorithms are implemented, such as: point-by-point comparison linear interpolation and circular interpolation, DDA linear interpolation and circular interpolation. The simulation results prove that the proposed design scheme of the hardware accomplishment technology of software is correct, which can enhance the portability and applicability of interpolation module...