Abstract: Bio-oil was prepared using wood powder，and then mixed with 50＃asphalt product and additives to obtain bio-binders with different bio-oil/asphalt ratios.The penetration，softening point，ductility（10 ℃）and other properties of the samples before and after RTFO aging were investigated.The bio-binder meeting the requirements of the specification was selected followed by preparation of bio-binder mixture.The rutting test，freeze-thaw splitting test，small beam bending test，low temperature bonding test were conducted for the mixture to investigate the effect of the amount of bio-oil blended into asphalt on the performance of the road bio-binder.The results showed that with increasing the bio-oil amount added，the penetration and ductility along with the low temperature crack resistance are improved；the softening point is reduced，indicating the negative effect for the high temperature performance.Compared with that of 50＃asphalt mixture，the maximum bending strain ratio of the bio-binder mixture with 10%w bio-oil is improved by 20.90%，the splitting tensile strain of freeze-thaw cycle samples increases by 12.56%，the water stability and low temperature performance are all improved； the bond ability is improved greatly while the high temperature performance is decreased in some extent.The properties of bio-binder mixture satisfies with the requirements of specification（JTG E20—2011）when the bio-oil content is 10%.

Key words: road engineering, bio-binder, experimental study, road performance, bio-heavy oil