Beijing's transportation commission released a new regulation on May 15 barring passengers from eating or drinking on the subway in a move intended to create a more comfortable space for travelers.
Uncivilized behavior, such as selling products or playing loud music, are also banned under the regulation.
Violations will be included in the passenger's credit record, and the person could be forbidden from taking the subway in the future, the commission said.
The commission also assigned special inspectors and supervisors to identify improper behavior on subway trains.
Prohibitions against smoking electronic cigarettes and using counterfeit tickets were also added to the rules.
Liu Daizong, China transport program director at the World Resources Institute, applauded the new measure and said that as an enclosed space, a subway car will be filled with odors if passengers are allowed to have food.
"These smells easily cause disputes between passengers, but there was no basis for law enforcement officers to get involved before," he said.
In January, a woman surnamed Wang sparked heated discussion online after she was filmed eating snacks and spitting out the food debris onto the floor of a car on Beijing's Line 13.
She was later found by netizens to be the same woman previously filmed eating chicken claws and spitting out bones in a Shanghai subway car. Netizens had dubbed her "chicken feet lady".
Other passengers asked Wang to clean up her mess but she refused, leaving the food packages in the subway car when she got off.
She was later detained by police in Beijing on suspicion of disrupting public transport.
Liu, who is also a member of the expert committee of the Beijing transport commission, said eating food on subways has become widespread worldwide, especially in big cities, as people commute to work.
Cities like Singapore, Nanjing and Xiamen have already banned drinking and eating on the subway, which provides a much cleaner environment for travelers, he said. Beijing, as an international metropolis, needs to catch up and provide a more civilized public space for commuters.
But some passengers in Beijing questioned the strictness of the new regulation.
Han Yanni, a 26-year-old white collar worker in the finance industry in Beijing, said drinking water and nibbling bread is her daily routine on the subway, especially in the morning rush.
"Except for onions or sunflower seeds, I can put up with most of the eating behaviors," she said. "Especially if they take a garbage bag for their trash."