Abstract: To explore the influence of biochar on the physicochemical properties of black soil in northeast China, a field experiment with five treatments was set up as 600, 1200, 1800, 2400 and 3000 kg/hm2 and CK. The results showed that biochar could increase soil porosity, electrical conductivity and water holding capacity while reduce soil bulk density in terms of soil physical properties. In terms of chemical nutrients, biochar could effectively increase soil organic carbon, available nitrogen, available phosphorus, and available potassium. Biochar could effectively increase the root activity and the total number of apical roots. In short, biochar could improve the physical structure of soil and other physical properties, increase the soil nutrient content, and raise root vigor and the number of root tips. However, the characteristics of biochar effect on different soils, the application amount and the effect degree need further study.