Abstract: The mass loss and radius contraction of T Tauri star under the role of the ejected material and gravitational contraction in the step of the slow gravitational contraction are studied. The evolutional equations determining the variation of mass and radius with time are established. The evolutional time scales of mass and radius are given. The influences of mass loss and radius contraction on the variation of the rotational angular velocity are given too. As example, the numerical effects of mass loss and radius contraction on the rotational relative angular velocity are estimated in Table. In addition the obtained results are discussed and concluded.