A hand gripper for a baseball player according to the present invention comprises: a body which is provided to be covered by the index finger, middle finger, and thumb of a user; and an elastic body which is fastened to the body to provide an elastic force. Here, the body has a partially cut-out ring shape, and includes an upper end, a lower end, and a gripping surface having a selected radius of curvature. The gripping surface is provided: to include a first boundary line which crosses the gripping surface in the lateral direction, and first protrusions repeatedly formed along the first boundary line; and such that the upper end and the lower end of the body can come into contact with each other as the body bends when the user applies force while gripping the body.