The present invention relates to a variable valve lift system that varies a valve lift in two stages by selectively rigidly engaging a tappet shim. The system includes a tappet shim receiving an operational force of a cam; a body for transmitting an operational force of the tappet shim to a valve; first and second supports, the first supports being provided on a surface of the tappet shim opposing the body and the second supports being provided on a surface of the body opposing the tappet shim, the first and second supports being supported by elastic members; first and second stoppers mounted respectively in first and second hydraulic pressure chambers, elastic members being interposed between the first and second stoppers and the body, and the first and second stoppers undergoing operation to selectively rigidly support the tappet shim; and a third stopper mounted in a third hydraulic pressure chamber, which is formed opposing the tappet shim, an elastic member being interposed between the third stopper and the body.