South Korea's wage gap between its high school and university graduates is smaller than the average of the Organization for Economic Cooperation and Development, data showed Monday.

According to data compiled by Seoul's Ministry of Employment and Labor, average wages of the country's university graduates are 37 percent higher than those of high-school graduates. The OECD average wage gap stands at 56 percent.

In terms of the wage gap, South Korea ranked 23rd among the OECD member countries.

Observers say this runs counter to the general perception in Korean society, which highly values academic backgrounds,that university graduates may get paid much more than those with high school diplomas.

Analysts speculated that the relatively small wage gap is attributable largely to the country's seniority-based wage system, from which blue-collar workers who can usually stay longer at a job benefit more than white-collar workers who tend to retire earlier.

Some observers pointed to the country's oversupply of college or university graduates in the job market is affecting the overall wage system. The percentage of Korea's high-school graduates opting for tertiary education was nearly 71 percent in 2014.

"Although most high-school students engage in a cut-throat competition to go to university, the reality is that the advantages of university graduation in the job market are gradually disappearing," Kwon Hyeok, professor at Pusan National University's School of Law, said. (Yonhap)