This study empirically identified the variables that influence the investment decisions of investors in the Korea Fund, which is listed on the New York Stock Exchange, and examined how efficiently Korean composite stock price information is reflected in the New York stock market. The research findings revealed that Korean composite stock price information, New York composite stock price information, and the interaction variable of these two variables were significant explanatory variables in explaining the price movements of the Korea Fund. However, these explanatory variables exhibited substantial differences in explanatory power across different time periods. In contrast, interest rates and exchange rates were found to be variables with virtually no explanatory power. Furthermore, the results of the stock market efficiency test indicated that when telecommunication networks between the two countries are adequately developed, Korean composite stock price information is efficiently transmitted to the New York stock market.