Effect of exercise has been studied on electrocardiography and stress behavioral parameters of 12 male Kangal shepherd dogs with ankyloglossia and 15 male Kangal shepherd dogs without ankyloglossia were compared. In this study, electrocardiography recordings were obtained from Kangal shepherd dogs with the holter device at resting state and during 15-min exercise. All data collection were conducted in the same environmental conditation. In addition, behavioral parameters captured with a video camera during resting state and the end of 15-min exercise period. While no statistical difference was detected in two groups in terms of all electrocardiographic parameters at resting state, statistical differences were detected in both groups in the P wave amplitude, T wave amplitude, duration of PR interval, duration of QT interval and heart rate parameters during exercise. Following 15-min of exercise, all stress parameters were observed in dogs with ankyloglossia, while only two parameters were observed at resting state. Following a 15-min exercise, without ankyloglossia dogs showed only two stress parameters, while no parameters were observed at resting state. This study will have an important area in the literature in terms of examining the electrocardiographic data and stress behavioral parameters of Kangal shepherd dogs with ankyloglossia.