Due to the irregular shape of shrimp, the automatic orientation is difficult. In view of the problems that the orientation link of shrimp pretreatment still relies on manual operation and lacks of orientation equipment, taking headless Penaeus vannamei as the research object, through the analysis of the shape and structure characteristics of the shrimp body, a head and tail orientation method was proposed, and the head and tail orientation mechanism of shrimp was analyzed. The theoretical study showed that it was feasible to orient shrimp’s head and tail by means of opposite rotation of parallel rollers. According to the shape parameters of shrimp, a directional conveying device for shrimp was designed. Medium-sized and large-scale shrimps were selected as the experimental objects. The single factor and orthogonal experiments were carried out with the roller gap, the conveying speed of pushing plate and the rotation rate of orientation roller as the experimental factors, and the orientation success rate as the index. Through the experiment, the influence law of each experimental factor on the orientation effect was explored, and the main parameters of the test device were optimized. The experimental results showed that the optimal parameters combination of the experimental device were as follows: the conveying speed of pushing plate was 40mm/s, the rotation rate of orientation roller was 90r/min, the corresponding roller gap of medium-sized shrimp was 10mm, and that of large-sized shrimp was 13mm. Under the optimal combination of parameters, the success rates of medium-sized and large-scale shrimp were 97.3% and 94.7%, respectively. The research can provide theoretical and technical support for the development of shrimp orientation equipment.