Koreans in their 20s are the least supportive of multicultural families, according to a survey by the Asan Institute for Policy Studies of 1,500 adults nationwide.

The survey, which was conducted last year, found that 67.5 percent of respondents believe more multicultural families in Korea strengthen the country's competitiveness. The proportion is down from 74.2 percent in a similar survey in 2011.

The change in attitude is most noticeable among people in their 20s and 30s.

In the 2011 survey, 75.1 percent in their 20s said they believe more multicultural families strengthen the country's competitiveness, but that fell to only 64.9 percent in the latest survey, the lowest among all age brackets.

A similar pattern appeared among respondents in their 30s, falling from 79.2 percent to 68.8 percent.

"Koreans in their 20s, who were thought to be more supportive of multicultural families, actually had the most negative views," said Kim Ji-yoon at the institute. "It appears that young people who are faced with an extremely competitive social atmosphere are getting more conservative in their views."