The Civil Service Commission - Regional Office No. 4 (CSCRO IV) was established through Memorandum Circular No. 1, series of 1975, in accordance with Presidential Decree No. 1 dated September 24, 1972 which provided for the Integrated National Reorganization Plan. Covering the Southern Tagalog Region, its territorial jurisdiction includes the provinces of Rizal, Cavite, Laguna, Batangas, Quezon, Aurora (sub-province), Marinduque, Oriental Mindoro, Occidental Mindoro, Romblon, and Palawan, and the cities of Batangas, Caloocan, Cavite, Lipa, Lucena, Manila, Pasay, Quezon, San Pablo, Tagaytay, TreceMartires, and Puerto Princesa.
With the establishment of the Civil Service Commission National Capital Region (NCR), CSCRO IV now covers only the provinces of Cavite, Laguna, Batangas, Rizal, Quezon, Occidental Mindoro, Oriental Mindoro, Marinduque, Romblon and Palawan.
First located at the Finance Department Building in Taft Avenue, CSCRO IV moved to the CSC Central Office in Batasan Hills, Quezon City in 1984. In 1990, it found new home, together with the CSC National Capital Region in Kaliraya Street, Quezon City. Under the helm of Director Rebecca A. Fernandez in June 2000, CSCRO IV relocated to 139 Panay Avenue, Barangay South Triangle Quezon City, its present location, after the Career Service Executive Board vacated the premises.