This article puts forward a multidomain resource allocation (MDRA) strategy for asynchronous multitarget tracking (AMTT) in heterogeneous multiple radar networks (HMRNs) with nonideal detection performance. The basis of the proposed strategy is to collaboratively coordinate the heterogeneous illumination resource (target-to-radar assignment, transmit power, dwell time, and signal effective bandwidth) of different types of radar networks, in order to minimize the total resource consumption in a nonideal detection environment, while satisfying the constraints of the specified requirements on AMTT and given system resource budgets. We derive the closed-form expression for the Bayesian Cramér–Rao lower bound with nonideal detection performance (namely, the probability of detection is less than 1), and adopt it as the criterion function to evaluate the asynchronous tracking performance of multiple targets. It is revealed that the formulated MDRA problem is a mixed-integer programming, nonlinear and nonconvex optimization model, due to its highly coupled Boolean and continuous parameters. By integrating the sequential quadratic programming and cyclic minimization algorithm, an iterative three-step solution methodology is developed to tackle the resulting optimization problem efficiently. Extensive numerical results are provided to verify that the proposed strategy consumes fewer resources to maintain the same level of AMTT performance in comparison with other benchmarks.