The value of 302 company stocks in which the National Pension Service holds more than a 5 percent stake came to 121.22 trillion won ($113.92 billion) as of the end of March, down 2.01 percent from the end of 2017, according to the data by FnGuide Inc.
The NPS' investment tally comes as the main Kospi fell 0.88 percent and the secondary Kosdaq grew 9.1 percent in the January-March period.
The losses were incurred by weak investor sentiments due to simmering concerns over trade wars between the United States and China, and the subsequent bleak business prospects for major companies, according to analysts.
Top cap Samsung Electronics Co., in which the NPS holds a 9.9 percent stake, fell 3.41 percent in the first quarter to 2.46 million won, effectively dashing the NPS value of shares it controls by 1.11 trillion won to 31.27 trillion won.
Naver, South Korea's top portal operator, tumbled 8.97 percent to 792,000 won, causing the value of the 10.83 percent stock owned by the NPS to shrink 278.4 billion won.
While the pension fund holds a 9.13 percent stake in the country's SK Telecom, the top mobile carrier's shares dived 12.55 percent in the January-March period.
The three aforementioned firms accounted for 65.7 percent of the total first-quarter losses for the pension fund, according to the data.
"We've managed our stock investment with long-term perspectives," said an NPS official, guarding against any hasty assessments.
This year, the NPS lowered its local stock investment guideline, setting the ratio at 18.7 percent from 19.2 percent in 2017. The move is part of its portfolio adjustment after last year's bullish market run, according to the official.(Yonhap)