The Korea CXO Institute, a market research firm, showed that foreign nationals accounted for 1.4 percent, or 94, of the 6,843 executives in the 100 listed companies.
Oh Il-sun, the director of the Korea CXO Institute, said the decline in the number of foreign executives in South Korea suggested that diversity and global corporate culture have been eroded at a time when companies are struggling to hire talented people, regardless of their nationality.
Data showed the number of foreign executives at South Korean tech giant Samsung Electronics came to 45 in 2018, or 47.9 percent of the total. The figure was a drop from 57 people in 2015.
Repeated calls to Samsung Electronics seeking comment went unanswered.
Hyundai Motor Co., South Korea's largest carmaker by sales, was a distant second with eight foreign executives in 2018, up from just two in 2015.
Kia Motors Corp., a smaller affiliate of Hyundai Motor, has two overseas top managers in 2018, up from zero in 2015.
Tongyang Life Insurance Co. came in third place with five non-Korean executives after being acquired by China's Anbang Insurance Group in 2016.
The data showed that LG Electronics, Samsung C&T, Samsung Engineering and SsangYong Motors had four foreign senior managers each in 2018.
Samsung C&T Corp., the construction unit of Samsung Group, had 13 overseas executives in 2015.
Oh said that 80 of the South Korean firms surveyed had no foreign executives at all in 2018, down from 82 companies in 2015. (Yonhap)