An optical imaging lens assembly includes, in order from the object side to the image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. The first lens element with positive refractive power has a convex object-side surface in a paraxial region. The fourth lens element with negative refractive power has a concave object-side surface in a paraxial region. The fifth lens element with positive refractive power has a convex image-side surface in a paraxial region. The sixth lens element with negative refractive power has a concave object-side surface in a paraxial region, a concave image-side surface in a paraxial region and at least one convex shape in the off-axial region of the image-side surface of the sixth lens element. The fifth lens element and the sixth lens element are aspheric lens elements.