Abstract: Detection of multiple unresolved targets is a frontier topic and pressing task in radar technology field. A signal fusion method of a T/R-R2 hybrid multistatic radar system is presented, target echo signal models of a monostatic radar receiver and two multistatic radar receivers are established, considering three-dimensional space situation, the signal fusion model is presented based on range information and the multiple unresolved targets are detected with maximum likelihood method, and the effects of SNR, number of targets, target fluctuation, detection threshold and hybrid multistatic radar geometrical configuration on the detection performance are analyzed. The Monte Carlo simulation results identify the effectiveness of the method. The detection method is presented under the assumed condition of Swerling II targets, but it is still suitable for Swerling 0 and IV targets.