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For the low efficiency and instability of anaerobic digestion of food waste, the effect of trace elements including iron, cobalt, nickel, selenium, molybdenum and tungsten on anaerobic digestion of food waste was investigated under mesophilic condition (37±1)℃ using CSTR reactors. The results showed that when hydraulic retention time was 40d, organic loading rate was 3g/(L·d), daily methane yield of the reactor with trace elements and control reactor reached to 7.1L/d and 6.7L/d, respectively. The methane concentration in two reactors was 62.7% and 61.6%, respectively. When organic loading rate increased to 4g/(L·d), the methane concentration of the control reactor decreased to 19.5%. However, it could keep stable at around 60% in the reactor with trace elements. Moreover, pH value in the control reactor dropped to 5.24 rapidly which demonstrated the failure of anaerobic digestion process, but it could perform stably at around 7.2 in the reactor with trace elements. A conclusion could be easily drawn that trace elements could improve the methane production efficiency and stability of anaerobic digestion process of food waste under the investigated conditions.