This paper investigates the trading behavior of individual, domestic institutional and foreign investors around earnings announcements in the Korean stock market. We first find that post-earnings-announcement drift (PEAD) exists in the Korean stock market for the post-2000 sample period, and that PEAD in Korea is similar in magnitude and persistence to PEAD in the US. Inspecting the trading behavior of the three types of investors before and after earnings announcements, we find that foreign investors’ trading behavior prior to earnings announcements predicts earnings surprise, and that their trades after earnings announcements appear to exploit PEAD to their advantage. In contrast, domestic institutional investors’ trades do not predict earnings surprise and their post-announcement trades do not seem to take account of PEAD. The findings suggest that foreign investors are superior to domestic investors in terms of informational advantage and/or investor sophistication. Somewhat puzzling is the trading behavior of individual investors, whose trades before earnings announcements predict earnings surprise in the opposite direction, and they continue to buy bad earnings surprise firms even after earnings announcements.