A window regulator apparatus may include a first operation part including a first housing with which a bar-shaped central shaft may be through-connected, and a first elastic member which may be connected inside of the first housing, a second operation part disposed inwardly of the first operation part and including a second housing with which the central shaft may be through-connected, and a second elastic member connected inside of the second housing to be slidably formed in a longitudinal direction of the central shaft from above the central shaft, and a connection part selectively connecting or disconnecting the first operation part and the second operation part to or from each other.