This study was aimed to investigate correlation between isokinetic shoulder muscle strength at diagonal pattern, serve speed and Functional movement screen (FMS (R)) scores in female volleyball athletes. Eighteen female volleyball athletes were involved into the study. Shoulder muscle strength at diagonal pattern were evaluated with the Biodex 3 (R) isokinetic dynamometer. Functional movement patterns were evaluated by sports scientist and physiotherapist specifically trained using standard FMS (R) Test Kits. Measurements were made with a pocket radar speed gun (USA) brand speed measuring device. There was a significant correlation between the peak torque values of shoulder flexion/abduction/external rotation and extension/adduction/internal rotation in dominant and non-dominant side of athletes at 60 degrees/sec and 180 degrees/sec angular velocities. (r= .553-.895 p <.05). In conclusion, a significant relationship was found among isokinetic shoulder muscle strength at the diagonal pattern, serving speed and FMS (R) scores in elite female volleyball players. We also recommend that it should be considered in the evaluation of shoulder muscle strength and strengthening programs since shoulder movements in volleyball players during serve and spike do not consist of internal and external movements in isolation and they occur in a diagonal pattern along with flexion-extension and abduction-adduction movements.