Distributed Coherent Aperture Radar(DCAR) is an important research direction in the field of radar at home and abroad. Accurate parameter estimation is the premise and core of good coherence performance. Based on the moving target model, a coherent parameter estimation method based on multi-pulse accumulation is proposed. The method performs fast-time and slow-time match filtering for multi-pulse signals, and obtains the results of multi-pulse coherent accumulation. Then the cross-correlation method is utilized to estimate the coherent parameters. The performance of parameter estimation and correlation under different numbers of pulses and different input signal-to-noise ratios are compared by simulation analysis. The simulation results show that the method is feasible and can effectively improve the performance of parameter estimation and coherence in low signal-to-noise ratio.