The six men and one woman, all in their 20s, went to the buffet-style restaurant at 5 p.m. on May 3 and stayed until it closed at 9:30 p.m., South China Morning Post reported.
A video posted on social media by one group member showed them gorging on seemingly endless dishes with hundreds of empty crab shells and cups used to serve mango pudding lying on surrounding tables.
Another group member told Bailu Video that he and his friends all had big appetites and claimed that people generally ate excessive amounts of food at their age.
Each person spent 160 yuan (US$23) for the buffet.
An employee at the restaurant said each customer could only eat for up to two hours, but the restaurant was crowded so staff forgot to ask the group to leave on time.
The video quickly went viral on Chinese social media, causing a stir among internet users due to the excessive consumption.
"I am worried about you all. Won't eating in this way hurt your stomach?" wrote one Douyin user.
The Chinese government passed a law two years ago to curb excessive food consumption and waste.