Method and system for controlling continuously variable valve timing

A method for controlling continuously variable valve timing (CVVT), may include determining whether a CVVT control is started, detecting a position of a cam and a position of a crankshaft when the CVVT control is started, determining whether the cam is positioned at a locking position based on the positions of the cam and crankshaft, determining whether the cam is controlled to be positioned from the locking position to an advancing position or a holding position, when the cam is positioned at the locking position, and when the cam is controlled to be positioned from the locking position to the advancing position or the holding position and when a condition for performing the CVVT control is satisfied, determining whether a cam torque is negative and performing predetermined CVVT control after waiting a predetermined time when the cam torque is negative.