This research will analyze the dynamics of the bat to determine a Sweet Spot. In this research, simplified geometry and abstract description of the bat shape were carried out and obtained the geometric equation of the bat. Then take the bat-ball system as the object of study. By using the Conservation of Momentum theorem, the theorem of Conservation of Angular Momentum and the recovery coefficient to build a dynamics model of a rigid body, then propose the Sweet Spot method and describe in determining the speed of the ball after the bat is hit. Starting from variations in the mass of the bat, center of gravity, and moment of inertia, it is concluded that the Sweet Spot will be in the long section above 0.564 m.