Materials and methods. Three groups of mentally disabled children of different age participated in dog-assisted therapy sessions twice per week for two months. Motor skills evaluation was based on the Bruininks-Oseretsky motor skills evaluation test (short version). Isometric torso muscle endurance tests were based on Ito, McIntosh and McGill. The ability to focus and memorise exercises and the ability to understand and perform them was also evaluated. Results. Movement perception and performance, as well as ability to focus and memorise the movement sequel improved after canine-assisted exercise sessions. The most significant changes in performance were observed in the torso muscle static endurance test, push-ups, fine motor skills, and coordination (p<0.001). Conclusion. Dogs can be successfully used as motivation for the performance of various task or to lower psychological tension and anxiety during exercise sessions. It is hoped that the results of this study will be used for the development of formal dog-assisted therapy guidelines for use in physical therapy with mentally disabled children.