Disclosed is an imaging lens unit that prevents the detachment of a cover from a holder. The imaging lens unit (200) is provided with a combination lens (6) and an external covering that is formed from at least the holder (2) and the cover (4) and covers the combination lens (6) from the outside, wherein the holder (2) and the cover (4) are connected by means of fitting members (70) that are integrally formed from a resin material and have, on both ends, a first fitting (78) that fits with a section of the holder (2) and a second fitting (80) that fits with a section of the cover (4).