AUSTRALIAN actor, writer and director Michael Pate has died, aged 88.

Pate, who spent seven decades in show business, died of respiratory failure.

Born in Sydney in 1920, Pate became an international star, appearing in more than 50 feature films.

He also guest-starred in more than 300 television shows in Australia and the US.

Pate began his career in 1938 writing and broadcasting for ABC Radio and producing book and theatre reviews for newspapers and magazines.

He spent almost 20 years in the US, appearing in countless TV shows, including various westerns.

Pate also appeared on other popular shows included Batman, Mission: Impossible, Get Smart and The Man from U.N.C.L.E, and was the first actor to play a slightly altered version of James Bond's CIA counterpart Felix Leiter in the television adaptation of Casino Royale.

He returned to Australia in 1968 to work as an associate producer for the Columbia Pictures adaptation of Norman Lindsay's Age of Consent.

He won two Gold Logies for the Seven Network and produced police series, pilots and variety shows for Australia's three commercial networks.

From 1971, he starred in the TV series Matlock Police and won a Penguin Award for best actor during his four years on the program.

Between 1982-1984 he joined forces with his son Christopher to co-star on stage in Mass Appeal.

The play toured Australia, culminating in a season at the Sydney Opera house.

Family friend Jacqui Bosanac said Pate had been working on a film script before he died and it was likely his son would finish off his father's work.

"Just previous to him going into hospital he was sitting at his computer," Ms Bosanac told the ABC.

"All he did was work ... he was working on a script which hasn't been finished and I think Christopher's going to try and finish it off."

Pate is survived by his wife Felippa Rock and son Christopher, both of whom are actors, and a number of grandchildren and great grandchildren.