Keystone Transform (KT) is a classical target range migration correction tool in radar.The existing KT implementation methods suffer from high computational complexity and dissatisfactory anti-noise performance.To solve the problems,a KT implementation method based on Fast Fourier Transform (FFT) interpolation is proposed.The basic idea is to convert the slow time echo to the frequency domain first,and then calculate the scaled echo through the continuous operations of frequency domain zero padding,Inverse Fast Fourier Transform (IFFT) and time domain decimation,etc.to complete KT decoupling.The simulation results show that the anti-noise performance of the proposed method is better than that of the existing KT implementation methods,and the computational complexity is significantly decreased.