According to the annual report by the Ministry of Science and ICT, the International Telecommunications Union said Asia's fourth-largest economy ranked first among 175 countries surveyed last year.
After losing its top spot to Denmark in 2015 for the first time since 2010, South Korea took back the lead the following year, the report added.
By sector, South Korea had high rankings in the percentage of households with Internet access, in the secondary gross enrollment ratio, in fixed (wired) broadband Internet subscriptions per 100 inhabitants and active mobile-broadband subscriptions per 100 inhabitants.
South Korea's combined exports of the ICT sector, however, came to $162.5 billion last year, the fourth largest in the world, the report showed. (Yonhap)