New Jersey State Highway 129 is a state highway in New Jersey, United States. It is a short connector between South Lamberton Road and U.S. 1 in Trenton, New Jersey.

Although New Jersey State Highway 29 is signed as a multiplex northbound from its southern terminus to the intersection with NJ 129, it is not a multiplex. But most of the northbound traffic comes from NJ 29 anyway, as very few items of public interest (Trenton Marina, a waste treatment plant, and an electric plant) are on South Lamberton Road, and no other intersections with any other streets exist south of the intersection with NJ 129.