PURPOSE: To evaluate clinical results between early fixation group and delayed fusion group in treatment of intraarticular fracture of 4th, 5th metacarpal base. MATERIALS AND METHODS: From March 2002 to December 2006, 21 cases of early fusion and 11 cases of delayed fusion of 4, 5th carpometacarpal joint were reviewed retrospectively or were included in this study. Average follow up period is 39.9 months. Bony union was checked by plain films at follow up. DASH-questionnaire, VAS pain scale, grip power and range of motion of 4th, 5th metacarpophalangeal joint were also checked at last follow up. RESULTS: In radiologic study, bony union was confirmed in all cases of two groups. Early fixation group showed better outcomes than delayed fusion group in range of motion, DASH-questionnaire and VAS pain scale with statistical significant (p<0.004). CONCLUSION: Because early fixation group showed better clinical outcomes than delayed fusion group, early diagnosis and proper surgical treatment are important for better outcomes in treatment of intraarticular fracture of 4th, 5th metacarpal base.