The brawl broke out between inmates on the jail's oval at 10.30am on Sunday, May 31.

Lithgow Correctional Centre staff and officers from the Security Operations Group responded to the incident, with officers dispersing the inmates and securing them in their cells.

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A Corrective Services NSW spokeswoman said a 35-year-old inmate was airlifted to a Sydney hospital for treatment for stabbing injuries.

Three other inmates, aged 26, 30 and 34 years, were transferred to regional hospitals for treatment to head injuries.

The men were transported to Lithgow, Bathurst and Nepean hospitals and the injuries were not stabbing related.

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While the Corrective Services NSW spokeswoman was unable to confirm how many inmates were injured during the brawl, Australian Community Media understands 12 were hurt.

The other eight inmates who were injured did not require hospitalisation and were treated by medical staff within Lithgow jail.

No staff were injured during the brawl.

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ACM understands CCTV footage within the jail will be reviewed by Corrective Services NSW and NSW Police as part of an investigation.

No charges have been laid as yet following the incident.