Chinese internet giant Tencent has limited the hours that children can play several of its most popular games.
It said the measures, restricting gaming depending on the player's age, were "to dispel parents' worries".
According to state media, there has been rising concern over Chinese children's excessive gaming habits.
Parents reportedly worry in particular about both the time and money spent playing Tencent's popular King of Glory mobile game.
From Monday, players aged under 12 will be allowed to log in to the game - whose name also translates as Honour of Kings - for only one hour a day, and not after 2100. Older children will be allowed to play for two hours.
Tencent claims the measures are the most strict in the country's booming online gaming industry.
Chinese state media quoted a company spokesperson saying that "even though as of now, China has not yet passed clear regulations dealing with gaming addiction, we have decided to take the lead".
The firm said it was also working on better implementation of its identity verification, so that those who had not yet completed the verification would not be able to play.
King of Glory is thought to have about 50 million daily active users, and there are numerous reports of parents and teachers expressing concern and frustration about children's gaming habits.
Reports say some children have been using their parents' credit cards to spend thousands of dollars on the game.
Excessive online gaming has been recognised as a problem in several countries, with authorities introducing different measures to tackle the challenge.
South Korea in 2011 launched a law to ban access for children under 16 from playing online games between midnight and 0600. In Japan, players get alerted by pop-up windows when they spend more than a certain threshold amount in a month.
Enforcement and reliable age verification remain the main obstacles to successfully addressing the problem, however.