More than 60 per cent of employers seeking junior clerks and telephone operators had an age limit of 30.

The survey, taken from job advertisements in six Chinese newspapers last month, also found that boutique managers often preferred to hire foreign workers who would accept lower pay.

The confederation's assistant general secretary, Leung Chi-shing, said: ''One of our members applied for a post as a salesgirl in a fashion chain store. The first question was how old she was, instead of work experience.'' The applicant, 28, was told that the post was offered to people aged up to 25, Mr Leung said.

Vice-chairman of the Clothing Industry Workers General Union Cheung Lai-ha said Hong Kong people were still good-looking after 30.

''While the retail industry says it cannot find suitable local staff, it sets harsh and unnecessary requirements. We have to ask why they hold the top position on the list for labour importation?'' Ms Cheung said age discrimination made it harder for workers in declining industries to change jobs. About 80 per cent of clothing workers were over 30. Because of discrimination, they were forced to stay with factories giving them two weeks' work a month.

''It's even more ridiculous that people who employ workers from skills-upgrading courses also want applicants in their 20s. But workers under 30 can't join,'' Ms Cheung said.

The confederation also revealed six ''harsh employers'' who required workers to be under 22. Three of those selected were the proprietors of cake shops.

''Maybe cakes from a prettier sales lady taste more delicious,'' the confederation's chief executive, Lee Cheuk-yan, said.

The confederation urged the Government to set up an anti-discrimination complaint unit and enact laws to prosecute employers who imposed age restrictions on job applicants. It said the Government should cancel an employers' quota for imported labour if harsh age restrictions had been set.