Disclosed herein is a lens actuating module. The module includes a housing having an accommodating space and a bush guide. A lens barrel is accommodated in the accommodating space and includes a lens and a barrel hook. A driving unit applies a driving force to a bush such that it is moved up in the direction of the optical axis, by pulling force of contraction of a shape memory alloy wire. The bush is guided by the bush guide and engages with the barrel hook. A rotary member is interposed between the housing and the lens barrel. A preload unit pulls the lens barrel in the direction of the optical axis such that the lens barrel moves 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.