A new microwave digestion/inductively coupled plasma mass spectrometry (ICP-MS) for simultaneous determination of 8 heavy metals including Zn, Cu, As, Pb, Cd, Cr, Hg and Ni in wastes of scale hoggery from livestock parks in Chongqing and its biogas slurry after anaerobic digestion, with which an all round, fast analysis of multiple heavy metals in biogas slurry was realized. From the experiment, Zn, Cu, As, Pb, Cd, Cr, Hg, and Ni were the dominating heavy metals in biogas slurry. The linear correlation coefficients for the heavy metals were between 0.999 89 and 0.999 98, indicating a good linear correlation. The determination limits were between 0.79 and 25.0 ng·L-1, recovery adding standard between 96.5% and 107.6%, RSD between 1.06% and 4.35%. These parameters revealed that the method has good precision and accuracy, which could be applied to the heavy metals detection in biogas slurry, and provide reference for its post-use.