Robert G. Margett (born May 8, 1929) is an American retired politician who was a California state senator until 2008. He represented the 29th Senate District, which includes parts of Los Angeles, Orange and San Bernardino counties. He is a Republican and served on the Budget and Fiscal Review Committee, Government Organization Committee, Natural Resources and Water Committee, Public Safety Committee and Transportation and Housing Committee. Formerly a mayor in Arcadia, California, he was first elected to the State Senate in 2000 and was re-elected to represent the 29th Senate District in November 2004. Previously he sat in the State Assembly, representing the 59th District, from 1995 to 2000.