SS Mission San Fernando was a Type T2-SE-A2 tanker built for the United States Maritime Commission during World War II.

Later the tanker transferred to the Military Sea Transportation Service as USNS Mission San Fernando (T-AO-122).

Mission San Fernando was laid down on 26 August 1943 under a Maritime Commission contract by Marine Ship Corporation, Sausalito, California; launched on 25 November 1943; sponsored by Mrs. Ruth B. Krohn; and delivered on 29 February 1944.

Transferred to the operational control of the newly created Military Sea Transportation Service on 1 October 1949 she was redesignated USNS Mission San Fernando (T-AO-122).

Designed to be a seagoing missile tracking station, she participated in the Apollo Project test series and into 1969 had continued in these duties.