Abstract: Forest and agricultural wastes are typical biomass materials,but it is costly to be stored and transported because of its loose structure and low energy density which can be improved by biomass charcoal pellets preparation through densification and sequent carbonization. In the paper,charcoal pellets are prepared from Chinese fir sawdust and sewage sludge with phosphoric acid as additives.The effects of the densification and carbonization process on the physical properties（apparent density and compressive strength）and yield of the resulted charcoal pellets are investigated. Meanwhile,the combustion characteristics and the ecological risk of the resulted charcoal pellets with better physical properties were also investigated. The results show that the die temperature and densification pressure have a similar impact on the physical properties of the charcoal pellets which arise first and then decrease with the die temperature and densification pressure increasing,while carbonization temperature has a complex impact on the physical properties of the charcoal pellets. The charcoal pellets produced under the die temperature of 80 ℃,die pressure of 100 MPa and carbonization temperature of 500 ℃ have the highest apparent density（1279.0 kg/m~3） and compressive strength（18.7 MPa）,far higher than those of commercial barbecue charcoal pellets. The yield of the charcoal pellet was negatively correlated with the carbonization temperature,decreasing from 72.0% at 300℃ to 57.2% at 600 ℃. The high physical properties and yield of charcoal pellet preparation can promote the effective and efficient utilization of biomass wastes to a certain extent.