F-18 fluoroacetate PET is proved to be a promising alternative to C-11 acetate which has been used for non FDG-avid tumors including prostate cancer, hepatocellular carcinoma, renal cell carcinoma, bladder carcinoma and brain tumors. Recently, F-18 fluoroacetate PET has also been used to image non-infectious inflammation induced by chemical or hypoxia. For better understanding the F-18 fluoroacetate PET in infectious inflammation compared with FDG PET, we evaluated the bacteria induced acute inflammation by Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) in six months-old Balb/c mice. The results showed that F-18 fluoroacetate obviously accumulated in lesions of bacteria induced acute inflammation and could be an alternative imaging agent of FDG to evaluate acute infectious inflammation. Furthermore, similar to FDG, F-18 fluoroacetate PET could also cause false positive results in cancer patients complicated with acute infection.