Milang looks likely to lose its part-time medical clinic, which would force residents of the area west of Lake Alexandrina to go to Strathalbyn or Goolwa for their health care.
At a public meeting attended by more than 60 people on Tuesday night, state MP Adrian Pederick vowed to do whatever he could to save the clinic.
"From my understanding the decision to cease operation at Milang was a business-related choice," he said in a statement afterwards.
"However, I am seeking to reduce the impact of this closure or prevent it completely, and together with the community I am investigating all options.
"I am committed to advocating on behalf of the residents of Milang and surrounding regions and I will continue to keep the community informed of my progress."
The clinic is currently open on Mondays, Wednesdays and Fridays.
Doctors travel from the Strathalbyn Medical Clinic to consult there.
The town has had its own medical service for 80 years, according to Mr Pederick.