SEVERAL factors that influence the preparation of ¹⁸⁶Re-Cefixime such as the amount of Cefixime and stannous chloride, pH, reaction time and reaction temperature were studied to optimize the labeling conditions to obtain the highest radiochemical yield of ¹⁸⁶Re-Cefixime. The radiochemical purity of Rhenium-186 was determined by paper chromatography, while the radiochemical yield and purity of ¹⁸⁶Re-Cefixime were determined by electrophoresis and high-performance liquid chromatography (HPLC). The maximum radiochemical yield of ¹⁸⁶Re-Cefixime was obtained (96±2.8%) using 2mg Cefixime, 0.3mg carrier added ¹⁸⁶Re and 0.5mg stannous chloride at pH 5.5, within 30min at room temperature. The bio-distribution was carried out on three types of mice (normal, sterile infected and bacterial infected). The results show that 186Re-Cefixime is more concentrated in the bacterially infected muscle (septic inflammation) than in the sterile infected muscle (aseptic inflammation). Therefore, ¹⁸⁶Re-Cefixime could be used to differentiate between septic and aseptic inflammation.