The victims were identified as 75-year-old Mohamed Ibrahim Rishad and his 65-year-old wife, Abdul Ayanul Rasamma, both residents of Maberiya, Ukuwela, Matale.
The deceased couple's niece, her three-year-old daughter, and the three-wheeler driver were also injured and are currently receiving treatment at the Matale District General Hospital.
Police suspect that the accident occurred when a rock fell from a 20-foot cliff and struck the three-wheeler as the group was returning from a funeral in the Millawana area.
Mahawela Police have launched further investigations into the incident.