A portion of the casing charge's fragments would strike the target plate and ricochet when it exploded close to or inside a steel structure, like a ship or manufacturing facility. Considering the high pressure, high temperature, and high strain rate during the impact, the kinematic characteristics of the ricochet fragment, such as ricochet velocities and ricochet angle, are challenging to describe using the existing methods. In this study, a novel theoretical model of ricochet fragment kinematics under oblique impact was proposed, and the corresponding initial assumptions and application conditions were presented. A series of oblique impact experiments was conducted to obtain the differences in kinematic characteristics under various impact velocities and impact angles. The parameters of the proposed theoretical model were determined. The accuracy of the theoretical model was verified by using 921A hull steel target plate. The average relative error and standard deviation of ricochet velocity were 7.4 % and 2.3 %, respectively, and the mean relative error and standard deviation of the ricochet angle are 11.2 % and 1.1 %, respectively. The results showed that the theoretical model can predict the ricochet velocity well, and the error of ricochet angle increased due to the different pile-up effect of different strength target plates, but it was still within the reasonable range. In addition, the effects of the impact velocity and angle on the ricochet velocity and angle were analyzed. When the impact angle was small, the ricochet angle and velocity were affected by both impact velocity and angle. When the impact angle increased to a certain Angle (>64.2°), the ricochet velocity only increased linearly with the impact velocity. The ricochet angle increased with the increase in the impact angle. When the impact velocity was less than 400 m/s, the ricochet angle increased with the increase in the impact velocity. When the velocity is greater than 400 m/s, the ricochet angle decreased with the increase in the impact velocity. When the impact angle was greater than 57° and the impact velocity was greater than 400 m/s, the ricochet angle was almost only related to the impact angle. The results indicate that the proposed model has good accuracy and can have high application value in terminal effects, safety engineering, and structural defense fields.