Abstract: Abstract: Heavy metals in soils are one of the most hazardous pollutants in the environment owing to their universality, concealment and irreversibility. Some universally think harmful heavy metals to mankind and environment are lead, cadmium, copper, zinc, manganese and chromium. They can destroy the normal functioning of soil, cause fertility degradation, lead to crop losses, crop quality declined and cause teratogenic carcinogenesis to human. Biochar (BC) is a passivation material and has demonstrated potential as a highly efficient emerging low-cost adsorbent used in the removal of heavy metals from soil or sewage. Experts and scholars have recently extensively researched biochars in environmental and agricultural applications. The adsorption mechanisms of biochars toward heavy metals indicate that the characteristics of biochars are strongly affected by the raw materials, pyrolysis time, and especially the pyrolysis temperature. Therefore, research on the heavy metal adsorption effect of biochars produced at different pyrolysis temperatures is very important in developing methods for treating sewage. To promote the sustainable usage of agricultural wastes like chicken manures and control heavy metal pollution, in this study, chicken manure biochars (BC200, BC400, BC600 and BC800) were produced through pyrolysis under oxygen-limited condition at the preparation temperature of 200, 400, 600 and 800 ℃. The physicochemical and structure characteristics of chicken manure biochars were detected by BET accelerated surface area and porosimetry system (This indicator is usually referred to as BET), scanning electron microscopy (This indicator is usually referred to as SEM), transmission electron microscope (This indicator is usually referred to as TEM), Fourier transform infrared spectroscopy (This indicator is usually referred to as FTIR), then the remediation effects of different pyrolysis temperatures of chicken manure biochars on heavy metal Cd and Pb were studied. The results showed that ash content, pH values, BET surface area, and average pore diameter increased with the increases of pyrolysis temperature, and the surface of chicken manure biochars had lots of irregular pore structure, mainly being mesoporous, while the yields of chicken manure biochars was significantly reduced with the increasing temperature (P<0.05). The adsorption of heavy metal Cd2+ and Pb2+ on chicken manure biochars included an initial fast sorption phase and a second slow phase, and Elovich equation could better simulate the processes of kinetic adsorption. The maximum adsorption capacities of heavy metal Cd2+ and Pb2+ at equilibrium reached 242.59 mg/g (BC800) and 52.02 mg/g (BC600), respectively. The application of chicken manure biochars significantly increased soil pH values (P<0.05), while the contents of heavy metals TCLP-Cd and -Pb were decreased, with the maximum reduction of 16.5% and 14.5%, respectively, in contrast with the blank treatments. When compared with CK (treatment without adding chicken manure biochar), the ratios of weak-acid-extractable, reducible fraction and oxidizable heavy metals Cd and Pb were decreased to some extent, but the percentage of residue fraction was increased by 5.49%-15.14% and 2.51%-6.30%, respectively. In summary, chicken manure biochars has a strong passivation effect on heavy metals Pb and Cd.