The problem of registration for multiple mobile sensors in a fusion system is considered. We develop a registration model for mobile sensors and implement the registration based on the nonlinear Kalman filter theory. A parallelized extended Kalman filter (EKF) structure is also derived in which the algorithm is parallelized and processed at each sensor. The parallelized EKF is shown to have the performance of a centralized system. It does not rely on a single central facility to perform and thus is less sensitive to sensor defects than the centralized system. Finally, computer simulations are used to show the effectiveness of the proposed registration algorithm.