The United States on Tuesday said it would impose duties of more than 500 percent on Chinese cold-rolled flat steel, which is widely used for cars body panels, appliances and construction.
China expressed "strong dissatisfaction" with the ruling, the Ministry of Commerce said.
"The United States adopted many unfair methods during the anti-dumping and anti-subsidy investigation into Chinese products, including the refusal to grant Chinese state-owned firms a differentiated tax rate," the ministry said in a statement posted on its website.
"China urges the United States to strictly obey World Trade Organisation rules and rectify its mistaken methods as soon as possible," it added.