The effects of liquid fertilization for concentrating near crop root system are to speed up the absorption of crops and improve the yield and quality of crops. Deep-into type liquid fertilizer applicator makes the liquid fertilizer into the soil. Aiming to meet the agronomic requirement of trajectory and posture of spray fertilizer needle of oblique type pricking hole mechanism when it got into and out soil and spray fertilizer needle did not damage crops, an optimization method of parameters reverse design was put forward based on Lagrange curve for cubic fitting trajectory. In order to obtain the ideal “xing hu” shaped trajectory for pricking hole, the posture of spray fertilizer needle got into and out soil was controlled by changing the coordinates for some types of value points on static trajectory, and then the kinematics model of spray fertilizer needle was established. The simulation software of reverse design and kinematics analysis was compiled, which was written by Matlab GUI development platform. Finally, the pitch curve of non-circular planetary gear trains, the angle of spray fertilizer needle got into and out soil and speed curve of spray fertilizer needle point along with the change of planet frame angle were got. High-speed photography bench was established and tested. The regulars of relative motion trajectory and absolute motion trajectory of spray fertilizer needle in different oblique angles of pricking hole mechanism were observed and analyzed. The results showed that as the oblique angles of institution increased, the lateral size of track of spray fertilizer needle remained the same, the longitudinal size of track of spray fertilizer needle was decreased, the trajectory curve of pricking hole mechanism was gradually inward contraction. The angles of spray fertilizer needle got into and out the soil were increased gradually when the soil depth was certain;as the oblique angles of institution increased, the width of hole mouth was increased.