An optical imaging lens assembly includes, 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 and a fifth lens element. The first lens element has an object-side surface being concave in a paraxial region thereof. The second lens element has positive refractive power. The third lens element has negative refractive power. The fourth lens element has positive refractive power. The fifth lens element has negative refractive power.