We have always abided by government rules and regulations, and our workers remuneration standards are in line with Chinese rules, McDonalds said in an e-mailed statement onj Thursday.
Yum, which operates KFC and Pizza Hut restaurants in China, also said that its payment standards were legal.
McDonalds pays part-timers four yuan (52 cents) per hour in Guangzhou, Guangdong province, where there is a minimum wage of 7.5 yuan. KFC pays 4.7 yuan and Pizza Hut 5 yuan, the report said.
International companies in China are increasingly being publicly criticised over ethnical issues.
Wal-Mart Stores Inc, the worlds largest retailer, last year allowed employees in China to unionise following criticism that the company exploited lax employee protection in the country to keep costs low.
All-China Federation of Trade Unions, a Chinese labour group, wants unions in 70% of foreign-funded businesses by the end of the year, from 60% in 2006, the official China Daily reported on January 5.
Taiwans Hon Hai Precision Industry Co, a maker of iPods for Apple Computer Inc, last June was accused by a local newspaper for forcing workers to work long hours for low pay.
Starbucks Corp has been under criticism in China for opening a store in Chinas Forbidden City, a move considered by some as an insult to Chinese civilization.
McDonalds, the worlds biggest restaurant chain, owns 789 restaurants in China, while rival Yum has more than 1,700 KFC restaurants in the country.