An imaging lens assembly includes a first optical element and a low-reflection layer. The first optical element has a central opening, and includes a first surface, a second surface and a first outer diameter surface. The first outer diameter surface is connected to the first surface and the second surface. The low-reflection layer is located on at least one of the first surface and the second surface, and includes a carbon black layer, a nano-microstructure and a coating layer. The nano-microstructure is directly contacted with and connected to the carbon black layer, and the nano-microstructure is farther from the first optical element than the carbon black layer from the first optical element. The coating layer is directly contacted with and connected to the nano-microstructure, and the coating layer is farther from the first optical element than the nano-microstructure from the first optical element.