An optical imaging lens assembly includes seven lens elements which are, in order from an object side to an image side: a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, a sixth lens element and a seventh lens element. The seventh lens element has an image-side surface being concave in a paraxial region thereof. At least one of an object-side surface and the image-side surface of the seventh lens element has at least one critical point in an off-axis region thereof. The object-side surface and the image-side surface of the seventh lens element are both aspheric.