Considering the problems, namely crops damage, large hole width and low fertilizer spraying efficiency of deep applicationtype liquid fertilizer hole applicator, a deep applicationtype inclined liquid fertilizer hole applicator was designed. Through the design of “oblique hole pricking and parameter reverse solution”, and based on the humancomputer interaction platform, the pricking hole mechanism of key components was designed, the structure and working parameters of the mechanism were optimized, and the movement form of fertilizer feeding interface of fertilizer spraying needle was analyzed. According to the technical characteristics of spraying fertilizer needle earthing and unearthing fertilizer, and to improve the efficiency of fertilizer delivery, the liquid fertilizer distribution mechanism, which was the key component, was designed by using the combined transmission form of “differential gear train transmission and space cam mechanism”. The movement model of the fertilizer outlet interface was constructed to analyze and satisfy the cooperative movement mechanism with the fertilizer inlet interface and reduce the complicated connection configuration of the fertilizer delivery pipeline. The field performance test of the deep applicationtype inclined liquid fertilizer hole applicator revealed a superior hole punching performance, the fertilizer was sprayed evenly, and the mechanical damage to crops was small. The hole width, crop damage rate, fertilization amount and fertilization depth were 45.0mm, 0.3%, 28.5mL/time and 102mm, respectively. All indexes were less different from the previous design and met the agronomic requirements.