In this paper, a distributed cubature Kalman filter algorithm based on spherical simple cubature rule is proposed for multi - radar real - time tracking of reentry targets. Firstly, the nonlinear Gaussian weight integral is approximated by the spherical simplex-radial rule. Then, the volumetric information is obtained by the equivalent linear error propagation method. Finally, the information fusion and consensus between the time update result of the single radar volume Kalman filter and the neighbor radar are obtained by the consistency algorithm, and the distributed spherical single diameter Kalman filter algorithm is obtained. The algorithm improves the tracking accuracy of the reentry trajectory target. The communication topology without information fusion center reduces the traffic and computation between the radar and improves the survivability of the whole system. The numerical simulation results verify the effectiveness of the algorithm.