The objective of the present study was to mitigate the greenhouse gas (GHG) emissions during composting of dewatered fresh sewage sludge (DFSS) employing biochar combined with zeolite (B + Z) and low dosage of lime (B + L). The 12% biochar was mixed at a 10%, 15% and 30% of zeolite and 1% lime, while without any additives was used as control. The results indicated that the combine use of B + Z was significantly increased the enzymatic activities and reduced the ammonia loss 58.03-65.17% as compare to B + L amended treatment, while CH4 92.85-95.34% and N2O 95.14-97.28% decreased than control. The B + L1% amendment significantly increased the organic matter degradation but the reduction was lower than B + Z and that could reduce the CH4 and N2O emission by 55.17-63.08% and 62.24-65.53% as compare to control, respectively. Overall our results demonstrated that 12% B + Z10% addition into DFSS can be potentially used to improve the DFSS composting by mitigation of GHG emission and nitrogen loss. (C) 2016 Elsevier Ltd. All rights reserved.