St. Joseph's established behavioral health services in 1974, as a unit on the third floor of St. Joseph's Medical Center in Stockton. The program grew rapidly during the 1980's, needing more space with future opportunity for growth of inpatient and outpatient services.

In 1988, St. Joseph's Behavioral Health Center began operation at 2510 North California Street, the former site of Oak Park Hospital, acquired by St. Joseph's in 1980. The site was a perfect location for a separate Behavioral Health Center, and opened with 35 beds and three units: Adult Intensive Treatment, Chemical Dependency, and Geropsychiatric services. Nearby space was leased adjacent to the hospital, to house the Outpatient Services Program in 1991.

St. Joseph's is committed to excellence in health care, serving Stockton and the surrounding communities of San Joaquin County, as well as Stanislaus, Merced, and Calaveras Counties. St. Joseph's Behavioral Health Center is a licensed, not-for-profit psychiatric and chemical dependency hospital with inpatient and outpatient services, staffed by board certified psychiatrists and experienced licensed professionals.