Background/Aims: Early detection of post-surgical infection is important to decrease mortality in patients after operation. Both C-reactive protein test and gallium-67 scan (gallium scan) are sensitive examinations in the detection of infection. In this study, we compared the diagnostic accuracy of the two modalities in the detection of infection after abdominal surgery. Methodology: Forty-six patients undergoing abdominal surgery were enrolled in this study. All patients received blood examination for C-reactive protein test and were referred to our department for gallium scan because of unknown fever after surgery. Results: Of the 46 patients with abdominal surgery, 22 (47.8%) were diagnosed to have infection including 6 intra-abdominal abscesses, 8 wound infection and 8 with both intra-abdominal abscesses and wound infection. To achieve better diagnostic results, C-reactive protein value of 2.8mg/dL was chosen as cut-off value. The diagnostic sensitivities for both gallium scan and C-reactive protein test were 100%. The diagnostic specificity of gallium scan was superior to C-reactive protein test (83.3% vs. 54.2%). The overall diagnostic accuracy of gallium scan and C-reactive protein test were 92.6% and 76%, respectively. Conclusions: Both C-reactive protein test and gallium scan have good sensitivity in the detection of infection after abdominal surgery. Gallium scan has better diagnostic specificity than the C-reactive protein test.