In the mid-2000s, as interest in Korea mounted among foreigners and the university expanded classes taught in English, there was a brief surge in foreign intake, but it peaked at 2,166 in 2014 and has been falling since.

At Oxford University, by comparison, the proportion is 17 percent among undergraduates alone.

The university only has 1,711 foreign undergraduate and graduate students, 388 of whom are exchange students. That is just around six percent of the student body, which is low for a university aspiring to international status.

SNU teaches far fewer classes in English than some private universities in Korea and lacks support for international scholars. Students are divided between those who support more classes being taught in English and those who are against accepting foreigners who cannot speak Korean.

Korea's top institution of higher learning, Seoul National University, is struggling to attract enough foreign students as it strives to boost its international kudos.

Rita Galves (24), who comes from the Philippines and is the vice president of the foreign students' organization at SNU, said, "Foreign students who come to SNU are surprised and disappointed when they find out how few classes are taught in English."

In some instances, professors advertised classes in English but changed their minds and ended up lecturing in Korean, either because their own or the Korean students' English was not up to scratch.

Galves, who majors in material engineering, said, "In some classes that are taught in English, key terms are explained in Korean or the professors' teaching assistants can't speak English and can't get the material across to foreign students."

Out of 3,480 undergraduate lectures, only 10 percent are in English, while at private Yonsei and Korea universities, the proportion is over 30 percent.

Gissele Chicas (20), who comes from El Salvador and began studying chemistry at SNU this year, said, "I chose to study at SNU because I was impressed by the advanced level of science education, but the classes in Korean are too difficult to understand and there are not enough taught in English."

An SNU admissions officer said if foreign students want to complete all the necessary credits under the present curriculum, they must listen to lectures available in Korean, but very few foreign students learn Korean before coming here. "It's getting more and more difficult to attract foreign students," the officer added.

Professors are divided about the need to offer classes in English, making it more difficult for the university to expand their number.

Noh Yoo-sun, a professor at SNU, said, "There are many students who have problems due to the language barrier since we accept foreigners whose Korean language skills are weak. But it's hard to ask prospective students to learn Korean before applying."

Disappointed foreign students leave with negative attitudes toward SNU, which discourages others from applying. "We need to offer systematic support, such as offering Korean-language classes to foreign students," Noh said.

