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Tools and methods that could lead to the recognition and motion analysis variables are helpful in understanding the movements and movement Sciences and It will be a vital part of movement and sport sciences laboratories. "Human motion analysis instrument based on joints angles in sagittal plane" was designed to provide information about the motion analysis that offers to researchers, educators and therapists. Once the instrument has been built according to the design of specialized electronic and mechanical engineers, tested until the fourth final design was made and it was registered on 21.05.1393 with number 83557. To check the validity, with using of motion analysis system with optoelectronic cameras and the instrument, 20 participants (10 males and 10 females) were asked to perform a throwing task. The root mean square error (RMSE) and Pearson correlation in the statistical 0.01 were used to assess the reliability and validity. The results indicate that the instrument is made applicable and appropriate validity and reliability so that the validity: 0.98 and reliability: 0.95 was reported.