Imaging lens module and electronic device

An imaging lens module, comprising at least one plastic lens element having an optical axis, an object side and an image side, wherein the at least one plastic lens element comprises, in order from a center to a peripheral region thereof:

• an optical effective portion, wherein the optical axis passes through the optical effective portion;
• and
• an outer peripheral portion surrounding the optical effective portion, wherein the outer peripheral portion comprises, on at least one of the object side and the image side:
• a plurality of groove structures;
• a contacting surface being an annular plane and perpendicular to the optical axis, wherein the contacting surface is connected to at least one optical element adjacent thereto;
• and
• a plurality of separation surfaces respectively surrounding each of the groove structures;
• wherein the groove structures and the contacting surface are located on the same side, there is an air gap between the groove structures and at least one optical element adjacent thereto, and the groove structures and the contacting surface located on the same side are not overlapped along a direction parallel to the optical axis;
• wherein a number of the groove structures located on the one of the object side and the image side is N1, and the following condition is satisfied:
• 30≤N1≤720.