The aircraft lost contact with airport authorities on a flight from the town of Masamba island about 30 minutes before it was scheduled to land in Makassar city.
Ferdinand Lumintaintang, Aviastar's flight operations officer, said that search and rescues were using signals from the pilot's and passengers' mobile phones on Friday night to try to locate the aircraft in a mountainous area.
Indonesia has a patchy aviation safety record and has had three major crashes over the past year, including an AirAsia flight that went down in the sea between Surabaya and Singapore on Dec. 28, killing all 162 people aboard.
In August, a passenger airliner crashed in Papua killing all 54 people aboard.
More than 100 people were killed in June in the crash of a military transport plane in the northern city of Medan, prompting the government to promise a review of the ageing air force fleet.
According to Aviation-safety.net, Aviastar has had four fatal incidents, including that of an British Aerospace 146-300 aircraft in the eastern province of Papua in 2009, killing all six crew on board.
Indonesia scored poorly on a 2014 safety audit by the U.N. aviation agency.