In an optical imaging lens set a first lens of positive refractive power has an object-side surface with a convex portion around the optical axis and a convex portion around its periphery, an image-side surface with a convex portion around its periphery, a second lens of negative refractive power has an object-side surface with a concave portion around its periphery, a third lens has an image-side surface with a concave portion around its periphery, a fourth lens has an image-side surface with a convex portion around the optical axis, a fifth lens has an object-side surface with a concave portion around its periphery, a sixth lens has an image-side surface with a concave portion around the optical axis and a convex portion around its periphery. The sum of total five air gaps AAG and a second lens thickness T2 satisfy AAG/T2≦3.6.