Abstract: Cadmium selenide can be used in the all optical framing camera and streak camera for ultrafast X-ray detection. Based on time-resolved pumping system with phase object, we studied the nonlinear properties of bulk cadmium selenide at 1030 nm under femtosecond pulse by two-photon absorption and got the nonlinear properties of two-photon absorbing coefficient, free-carrier absorption cross section, and free-carrier life time. According to the experiment, the nonliear response of cadmium selenide is a combination of bound-electron effects and two-photon-induced free-carrier effects. The Kerr effect and the two-photon excitation are transient, and the free-carrier recombination lasts for a long time. The experiment has provided useful data of carrier parameters and images foe design.