A lens module for being fixed to a substrate by UV glues includes a lens barrel and a lens holder integratedly formed at a bottom of the lens barrel. The lens barrel has a hollow receiving groove for receiving an optical lens therein. The lens holder defines a containing cavity communicating with the receiving groove and penetrating through a bottom thereof to form a plurality of inner walls surrounding the containing cavity. The lens holder further defines a plurality of outer pillars spaced from each other and arranged apart from outer peripheries of the corresponding inner walls to define gaps therebetween. The UV glues are distributed to a bottom of each outer pillar so that ultraviolet lights can pass through the intervals between the outer pillars to adequately irradiate and solidify the UV glues for making the lens module fixed to the substrate firmly.
