Kooser State Park is named for John Kooser and his descendants who in 1827, settled in the western end of the park near Kooser Spring. This original 920-acre tract was sold to the United Lumber Company in 1913.
After the lumber company declared bankruptcy, the Commonwealth of Pennsylvania purchased 2,730 acres, which included 720 acres of the original Kooser tract, for use as a forest reserve. In 1920, this area became part of Forbes State Forest.
With the advent of affordable automobiles and the growing popularity of auto camping, the Kooser Public Camp was developed at the Van Dyke Spring in 1925. The camp was popular with travelers along PA 31 and included an open front lean-to, comfort station, tables and benches, fireplaces, and garbage container.
In 1933, an area west of the Kooser Public Camp was selected as a site for a Civilian Conservation Corps (CCC) Camp S-99-PA.
From 1934 until 1940, the CCC boys built a wooden and earthen dam creating a four-acre lake, beach, and bathhouse, a road around the lake, nine log cabins, trails, picnic areas, shelters, pavilions, park office, tree nursery and arboretum, as well as made improvements to Kooser and Van Dyke springs.
A tornado in 1945 caused severe damage to the CCC facilities. From 1952 until 1954, the remaining CCC buildings were leased to a church group for use as a camp known as Camp Kincora.
Major redevelopment of the park took place from 1955 through 1957, and during 1962, the Bureau of State Parks took over the operation of the park.