There have been geopolitical risks due to national peculiarities in the Korean stock market. This is a
fundamental background in which the word 'Korea discount' has emerged in the Korean stock market and
has influenced the domestic stock market in a variety of ways depending on the nature of the issue.
Among them, North Korea's nuclear test issue is a major conflict that can maximize geopolitical risk. This
study empirically analyzed the effect of North Korea 's nuclear test issue on the stock market of a specific
industry using the event study methodology as an background of efficient market hypothesis. Specific
industries are the chemical, manufacturing, and machine that have been shown to respond sensitively to
North Korean nuclear issues in previous studies. By applying the event study methodology, we divided
stocks by industry and extracted the regression model for about 120 days before the nuclear test and measured the abnormal return rate by the industry in which the appropriate regression model was derived.
Through this, investors can make appropriate investment decisions by referring to the fluctuation records of
the industry groups to which their investment items belong, rather than the outsider opinion that the North
Korean nuclear issue has little impact on the KOSPI.