Abstract： Objective To study the impact of complicated intra-abdominal infections on albumin synthesis rate. Methods Eight patients with complicated intra-abdominal infections associated with intestinal fistula were admitted to the Research Institute of General Surgery at the Jinling Hospital between December 2009 and October 2010. Eight healthy volunteers matched for age, sex, and amino acid pool and from albumin were determined by gas chromatography/mass spectrometry analysis. Results Both plasma total protein concentration (62.2 ±1.0) g/L and plasma albumin concentration (32.5 ±4.0) g/L in patients with complicated intra-abdominal infection were lower compared with controls[(74.2±1.7) g/L and (46.1±2.6) g/L, both P<0.05]. Body temperature, neutrophil count and plasma C-reactive protein concentration in patients with infection were significantly greater than the levels in control subjects(P<0.05). Albumin synthesis rate in patients with intra-abdominal infection was significantly lower than that in the control group[(5.3±1.6)%/d and(7.8±1.2)%/d respectively, P<0.05]. The measurement of plasma free amino acid concentration showed that plasma glutamic acid level was greater than that in control subjects, and that plasma phenylalanine and proline levels were lower than those in controls. Conclusion Complicated intra-abdominal infection inhibits albumin synthesis rate in patients with intestinal fistula, which may partially contribute to the decrease of plasma albumin concentration.