Midland Park was incorporated as a borough on September 6, 1894, at the height of the "Boroughitis" craze then sweeping through Bergen County that led to the creation of over two dozen new municipalities in the county in that one year alone. The new borough consisted of portions of both Franklin Township and Ridgewood Township. The borough expanded in April 1920 by adding another part of Franklin Township. In a referendum held on June 9, 1931, Midland Park acquired additional land from Wyckoff Township (which until 1926 had been known as Franklin Township). The borough says that Midland Park was named after the New Jersey Midland Railway, which operated the railroad passing through the area of the borough in the 1870s, though elsewhere the name is said to be based on being situated "amid Bergen hills".