Allamuchy Township is a township in Warren County, New Jersey, United States. As of the 2010 United States Census, the township's population was 4,323, reflecting an increase of 446 from the 3,877 counted in the 2000 Census, which had in turn increased by 393 from the 3,484 counted in the 1990 Census.
Allamuchy Township was incorporated as a township by an act of the New Jersey Legislature on April 4, 1873, from portions of Independence Township. The township's name comes from the Native American word "Allamachetey", meaning "place within the hills".