SHANGHAI, June 5 -- A NEW survey reported that two out of three Chinese people believe premarital sex is acceptable, reflecting a growing liberalism in social mores.

The study, conducted by the socio-sexology institution of Renmin University, explored changes in sexual attitudes from 2000 through last year, China News Service reported yesterday.

Among the 6,010 respondents from 21 provinces and municipalities, 63.8 percent said premarital sex is not immoral, up from 55.7 percent in 2000, the report said. Those polled were between 18 and 61 years old.

Slightly more than 60 percent of the female respondents said premarital sex is acceptable, an increase of 11.3 percentage points from 2000, outpacing the rise in men. (China News did not report the figure for males.)

Two-thirds of middle-aged respondents had no problem with premarital sex, as did more than 70 percent of those in the middle-income ranks.

Pan Suiming, dean of the institution, said that about 70 percent of the country's social and cultural "elites" accepted premarital sex, the fastest-growing such group over the survey period among all social classes.

Pan also said that nearly 30 percent of people older than 27 are still single and live without having sex.

The survey, which Pan supervised, interviewed people from different socio-economic backgrounds, including the middle aged, the middle class, white-collar workers, senior officials, technicians, teachers and intellectuals.

China will conduct its first survey on the sex lives of middle-age couples this year, according to an earlier report.

The survey, to be carried out by the China Population Communication Center and the pharmaceutical company Eli Lilly & Co, will ask couples if they have sufficient intimacy in their relationships and if their sex lives are satisfactory.

Ma Xiaonian, a professor at the China Sexology Association, said the intimacy index would indicate if sexual harmony promotes closer relationships, and the survey could also help guide middle-age couples in enjoying their marriages.

An annual international survey released in April by the world's biggest condom maker, Durex, found that 42 percent of the Chinese respondents said they were satisfied with their sex lives.

The research revealed 46 percent of Chinese men said they were happy in bed but only 35 percent of the women were satisfied.