Deukmejian, a Republican, served as the 35th governor of California from 1983 to 1991.
His former chief of staff Steve Merksamer says Deukmejian died Tuesday of natural causes.
Tributes from the state's political figures have begun pouring in.
Tremendously sad to learn of the passing of Gov. Deukmejian. He served our State w/ honor + distinction, including signing legislation prohibiting California pensions from investing in apartheid South Africa. George’s leadership moved the arch of history + changed the world! pic.twitter.com/DZcJZge2Ay— Gray Davis (@GovernorDavis) May 8, 2018
"Tremendously sad to learn of the passing of Gov. Deukmejian," former Gov. Gray Davis wrote on Twitter. "He served our State w/ honor and distinction, including signing legislation prohibiting California pensions from investing in apartheid South Africa. George's leadership moved the arch of history and changed the world!"
Deukmejian was known as a conservative who favored law-and-order policies and budgetary discipline, earning him the nickname "The Iron Duke."
Overall he spent nearly three decades holding office in Sacramento, serving terms also as state attorney general and in the state Senate and Assembly.
Deukmejian ran a law-and-order administration from 1983 to 1991, expanding the state prison system, bringing the left-leaning California Supreme Court to the center and supporting tough, anti-crime legislation.
He earned his nickname from his Republican supporters in the Legislature for his resistance to spending increases and his willingness to veto spending proposals.
Deukmejian was born June 6, 1928, in New York, not far from the state capital of Albany. After earning his law degree at St. John's University, Deukmejian was drafted into the US Army, where he was assigned legal duty.
After ending his service, Deukmejian returned to the US and established a law practice in Southern California.
Deukmejian was elected to the Assembly in 1962 and served in the lower chamber until 1967. That year, the voters of Los Angeles sent him to the state Senate where he would serve until 1979. He followed that up by serving as the state attorney general from 1979 to 1983.
Deukmejian was elected governor in 1983, defeating Democrat Michael Curb, who served as lieutenant governor under Jerry Brown.
Deukmejian would go on to serve two terms. The California State Library lists his accomplishments as promoting sound economic policies that led to the creation of more than 2.8 million new jobs, making education a priority for the state and creating a workfare program.
Deukmejian was also notable for being the state's only governor of Armenian descent.
Since serving as governor, Deukmejian remained active in the community, particularly around his home in Long Beach.
Deukmejian is survived by his wife of more than 60 years, Gloria May. The couple had two daughters and one son together.
The Associated Press contributed to this report.