China used a meeting of the WTO's technical barriers to trade committee to raise the issue of a ban imposed by India, stopping short of launching a formal trade dispute.
The row has been closely watched as an example of trade tensions between developing countries at a time when fears are growing that protectionist measures could worsen the economic crisis, a foreign news agency reported.
A participant at the meeting said that China has told the trade committee that the ban was discriminatory and violated basic WTO principles.
India said it had held talks with China on the issue and it hoped forthcoming high-level talks would resolve the matter.
Chinese Vice-Minister of Commerce Zhong Shan is visiting New Delhi this week.
India imposed a six-month import ban on toys from China in January, citing the public interest, later making it clear that it had health and safety concerns about the products.
On March 2, India relaxed the ban to allow shipments certified by global safety agencies.