About 45 million trips are expected to made to or from Shanghai during chunyun, the Spring Festival travel rush from January 21 to March 1.
About 24 million trips will be made out of town and there will be some 20 million arrivals, the traffic authority said.
After Spring Festival, the traffic authority expects the peak flow to be on February 9 when the holiday is about to end.
Some 1.1 million cars are expected to leave town via the expressways every day during the travel rush.
The highway toll fee is waived from February 4 to 10.
Train tickets from Shanghai to Anhui Province before Spring Festival have mostly sold out, said Shanghai Railway Station.
There are still tickets remaining to places in southwestern China like Chongqing, Sichuan and Guizhou.