The invention discloses an electro-Mechanical CVT (Continuously Variable Transmission) clamping force adjustable mechanism. An output shaft of a clamping force adjustment motor is connected with a force transfer pressure plate through a gear reduction mechanism; a clamping force adjustment spring is arranged between the force transfer pressure plate and a driven wheel dynamic plate; a thrust bearing is arranged between the clamping force adjustment spring and the driven wheel dynamic plate; the clamping force adjustment spring acts a clamping force on the driven wheel dynamic plate through the thrust bearing; a pressure spring is arranged on the driven wheel dynamic plate; an auxiliary spring is further arranged on the force transfer pressure plate; and an acting force of the auxiliary spring on the force transfer pressure plate is opposite to an acting force of the clamping force adjustment spring on the force transfer pressure plate. According to the electro-Mechanical CVT clamping force adjustable mechanism provided by the invention, the clamping force of the electro-Mechanical CVT can be changed in real time according to the magnitude of CVT transmitted torque, can adapt to the CVT transmitted torque, and is prevented from always keeping at a maximum transmitted torque state, so that the system life is prolonged, the transmission efficiency is improved, and the electro-Mechanical CVT clamping force adjustable mechanism has a larger application value.