As a lower bound on mean square error of parameter estimate, the Cramér-Rao lower bound (CRLB) is generally used to decide to what degree a suboptimal estimate method is close to its optimal fashion. With the assumption of coordinated turn maneuver, a generic approach for target tracking CRLB calculation was investigated under the conditions of active and passive measurement, and the essential reason for possible CRLB's sudden increase caused by maneuver was also analyzed from the perspective of matrix theory, which provides an effective measurement for performance assessment of estimate methods used in maneuvering target tracking. Finally, simulation example for CRLB calculation was presented.