Shipments of imported designer clothing from reputed labels such as Hermes and Versace were impounded by China after they found that the shipment contained potentially hazardous chemicals.
Among 85 batches of imported clothes tested, 48 batches containing items from 30 international brands from 11 countries were found to be sub-standard, the industry and commerce department in eastern Zhejiang province said.
The hazards included excess levels of chemicals such as formaldehyde, which the agency said could cause respiratory and skin problems and in some cases lead to cancer.
Authorities have impounded the goods and started an investigation into Chinese merchants selling the "sub-standard" products, the department said in a statement on its website.
The brands affected also included Hugo Boss, Dolce & Gabbana, Tommy Hilfiger and Zara.
China has itself been rocked by a series of product-quality scandals involving domestically produced goods in recent years, ranging from dangerous tyres to toys coated with toxic lead paint.
In 2008, the nation's dairy sector was devastated by a scandal involving baby formula contaminated by the industrial chemical melamine, which was illegally added to milk supplies to give it the appearance of a higher protein content.
The government said at least six infants died and more than 300,000 suffered health problems as a result.