The Nepean Medical Association began in 1988 as an organisation to represent local medical practitioners.

Originally the Nepean Hawkesbury Medical Association, as a result of the growth in the Nepean area it became a separate entity in 1988. It was incorporated on the 15th February 1996.

Full membership is open to all registered medical practitioners. Changes to the constitution in 2011 allowed associate membership for medical students.

Previous Presidents include Dr Michael Dally, Dr Laurie Bott, Dr Adrian Sheen and Dr Barry Kroll. The annual dinner, held in August or September of each year, is in association with and sponsored by Barratt and Smith Pathology.

The NMA in association with Medlinks produces an annual Medical Practitioners Directory that details local medical services and is distributed free.