[Purpose] This study investigated the relation between motor imagery and hamstring strain in rugby players. [Subjects] The participants of this study comprised 21 university rugby players (42 legs). [Methods] The motor imagery capacity of the subjects was evaluated using mental rotation and various motor exercises. The subjects were followed up 6 months after the measurements were taken, and the hamstring strain occurring in the intermittent period was investigated. [Results] Seven legs of 6 players (7/42, 16.7%) showed symptoms of hamstring strain within 6 months. In addition, all these subjects had medial hamstring injury that had occurred in a non-contact fashion. A significant difference was observed in the reaction time between the strain and non-strain groups for identifying photographs of the plantar view of the foot at an orientation of -90°. Furthermore, a cutoff value of 2.48 sec for this reaction time could predict hamstring strain by discriminant analysis. [Conclusion] Capacity of motor imagery influences the development of hamstring strain.