The China Seismological Bureau (CSB) on Sunday revised the magnitude of southwest China earthquake from 7.8 to 8.0 on the Richter scale.
The magnitude was revised upwards after specialists carried out "real-time and detailed measurements of the quake according to international practices," the bureau said.
Chinese earthquake experts have also referenced quake data provided by other seismological observatories around the globe, it said.
The US Geological Survey and Japan Meteorological Agency has put the magnitude of the tremor at 7.9.
The first report of by CSB set the magnitude at 7.6 which was shortly upgraded to 7.8 after the quake hit Sichuan Province on May 12.
The quake, whose death toll has exceeded 32,000, has seriously damaged buildings, bridges and other public facilities in an area of more than 100,000 square kilometers.