A continuously variable valve lift system includes a driving swing arm, an adjusting member, an adjusting swing arm and a camshaft. The driving swing arm is provided with a first connecting part, the adjusting member is provided with a second connecting part, and the adjusting swing arm is provided with a third connecting part, wherein two sides of the second connecting part abut against the first connecting part and the third connecting part, respectively, the second connecting part abuts against the third connecting part to form a spiral surface therebetween, and the adjusting member is further capable of sliding along an axial direction of the middle shaft, and the camshaft contacts with the adjusting swing arm.