Italian luxury brand La Perla has failed the most quality tests among all the brands of imported clothes in China in 2014, the country's quality watch dog said in a report on Monday.

66 batches of cargo imported to China in 2014 by La Perla, the luxury Italian women's clothing company specializing in lingerie, failed 24.24 percent of the tests it was subjected to, the General Administration of Quality Supervision, Inspection and Quarantine said in a report on Monday.

American clothing manufacturer American Apparel came second in the ranking of international brands that failed the most quality tests, while Italian fashion brand Cavalli came third.

Fashion brand Dolce & Gabbana and Armani were also on the top 10 list of brands with clothing that failed the quality tests, failing 13.12 percent and 10.76 percent of quality tests by the authority, respectively.

Fast fashion brands Forever 21, Mango and Old Navy were found to have failed a large number of quality tests.

Fiber composition, color fastness and pH levels are major reasons for failing the tests, the authority said.