Arlen Foster Gregorio (born September 11, 1931) is an American attorney, politician and commercial mediator.

Naval Air Officer for three years in the 1950s[1] receiving the China Service Medal for combat duty.

[3] He was a partner in general law practice from 1958 to 1970 and held the position of Assistant City Attorney for San Bruno from 1962 to 1970.

[7] During his two terms in the Senate (1970 - 1978),[2] Gregorio authored laws dealing with legislation and campaign finance reform, alcohol and drug abuse, the arts,[2] environment, education and health.

[16][17] In that political contest, Gregorio and his opponent, Becky Morgan, set a "new Senate campaign spending record" of $1.6 million.

[21][22] He appeared with Maharishi Mahesh Yogi, Ellen Corby (The Waltons), Harold H. Bloomfield, Clint Eastwood and others on two episodes of the Merv Griffin show in 1975.