One million people have been told to leave their homes and 18 people have reportedly been killed after Typhoon Lekima stuck the coast south of Shanghai.
Another 14 people are missing after Lekima hit land in Zhejiang province, state media said.
It added more than 200 houses collapsed and 3,200 were damaged.
The super storm has brought winds of 116mph (187kmph) to the eastern region of China.
Local media said a river was blocked by a landslide then rose 10 metres before breaking through the debris, flooding homes.
Video from Zhejiang Province shows the moment a family was rescued by emergency services after water deluged their street.
People are staying in emergency centres set up in the wake of the storm to deal with those who have lost their homes through flooding.
Dramatic video captured the storm spinning on the horizon as it approached Zhejiang province.
State TV said 3,023 flights in Shanghai, Hangzhou and other cities and some train services were cancelled.
Authorities in Shanghai shut down the high-speed magnetic levitation train to Pudong International Airport.
An estimated 2.7million homes have lost power because of the storm.