An apparatus for driving a lens in a camera includes a lens module installed in a reciprocating and sliding manner in an inside of a lens barrel, a lead screw installed on the lens barrel, for being rotated by a driving motor, and a power transferring member assembled on the lens module and equipped with a tooth-shaped part that corresponds to a tooth shape of the lead screw. The lens module has a lens and a slider having a mounting unit for mounting the lens and receiving the power transferring member in a movable manner. The mounting unit has a through groove in which one end of the power transferring member is fit and supported and a slit groove in which the other end of the power transferring member is fit to be supported for being movable in a direction perpendicular to the movement direction of the slider.