Abstract: For the requirement of making full use of the limited resource in real application, this paper proposes a power allocation scheme for 3D target tracking in multistatic radar systems. Firstly, the Bayesian Cramer Rao Lower Bound (BCRLB) for 3D target tracking mean square error is derived and utilized as a criterion for the power allocation strategy. Then, the resulting nonlinear convex problem is solved by gradient projection algorithm. Finally, simulation results suggest that the tracking accuracy of the whole system is enormously improved by using the proposed algorithm compared with the results achieved with equal power allocation.