A lens actuating module. The module includes a housing and a lens barrel. received in an accommodating space of the housing and having a lens therein. A driving unit applies a driving force to the lens barrel such that the barrel can be moved up in an optical axis direction by a pulling force of contraction of an SMA (shape memory alloy) wire fixed to the housing. A rotary member is interposed between the housing and the lens barrel. A preload unit pulls the lens barrel in the optical axis direction such that the lens barrel can move down to an original position, and pulls the lens barrel in a direction perpendicular to the optical axis to maintain a contact of the lens barrel with the rotary member. The lens barrel is moved by the contracted or extended amount of the SMA wire, thus realizing a simple structure and miniaturization.