This study empirically examined the effects of Merger announcements on stockholders wealth in KOSDAQ. The abnormal return(AR) and cumulative abnormal return(CAR) surrounding the merger announcement date are used to assess whether M&A activities enhance the stockholders wealth of bidding firms. The empirical results are as follows. First, bidding firm, on average, revealed statistically significant 2.08%(t-value: 2.35) of AAR on the announcement date and 4.44%(t-value: 1.79) of CAR(-10,+1) and 2.90%(t-value: 1.77) of CAR(-1,+1) by market model procedure. Second, venture firm, on average, gained higher shareholder wealth than general firm, especially revealed statistically significant AAR(0), AAR(+1), CAR(-1, +1), and CAR(-10, +1).