In a tennis game, effective and efficient biomechanics motion is very important to produce maximum explosive power. In addition to blocking the flow of ball power, the wrong stroke motion is also expected to cause injury. This study uses R&D with a sampling technique using purposive sampling of 10 national athletes. The instrument developed is biomechanical motion including foundation, rotation, force position, impact and follow through. The results show that the most crucial aspect of the foundation is how athletes use the forehand grip correctly, namely the semi western. Correct rotational motion plays an important role in gathering energy by means of good and fast body elasticity. A good strength position utilizing the position of the shoulders, chin, inactive hands, body position and elbows must carry out their functions properly in a regular series of movements. The correct impact is done at perfect momentum and the eyes are focused on the ball, the racket is slightly horizontal, the weight is transferred forward through the left knee and the shooting distance is not too far or too close to the body. The folow trough should be accelerated and let it flow naturally until it runs out to the sides. The conclusion of the forehand technique if done with the correct biomechanical motion will affect the power of the stroke, the more effective the movement, the greater the power generated