The accident occurred on the Baikal federal highway near the town of Bolotnoye.
According to preliminary information, the 38-year-old driver of a Honda Honda HR-V lost control of his vehicle on the icy road, and swerved into the oncoming lane.
"The driver and his four passengers died immediately. Three of the victims were young men, aged 18, 20 and 22," the police press service said.
In the other car, a Renault Megane, the driver and one passenger survived with injuries. The second passenger, a 38-year-old woman, died on site.