Author Bryce Courtenay has been given only months to live after being diagnosed with cancer.

The award-winning writer has revealed on his Facebook page that he has been diagnosed with terminal gastric cancer.

Author Bryce Courtenay. Credit:Narelle Autio

"It is with great sadness that I am writing to let you know that Jack of Diamonds, my new book due out in November this year, shall be my last," Courtenay wrote.

"I have been diagnosed with terminal gastric cancer and am expected to have only some months to share with my adorable wife, Christine (Gee).

"You will be pleased to know that I am currently feeling well and am keeping busy gardening, and writing a collection of short stories, as well as being with our beloved pets."

The 79-year-old author's books include The Power of One, The Potato Factory and Jessica.

He lives in Canberra.