Abstract: 22MnB5 hot press forming steel was micro-alloyed by composite addition of 0.04wt% niobium and 0.04wt% vanadium. The microstructure, tensile properties, hardenability and extreme tip cold bending performance of the tested steel before and after micro-alloying were studied and compared. The effect mechanism of niobium and vanadium micro-alloying on the properties was analyzed. The results show that the microstructures of the tested steel before and after micro-alloying consisted of whole martensite and had obvious martensite strip. The microstructure after micro-alloying was finer, the length of the martensite strip was shorter, and the tensile properties were improved slightly. The niobium and vanadium micro-alloying improved the hardenability of the tested steel effectively, whose hardened layer depth was improved from 3-5 mm before micro-alloying to 13-14 mm. After the niobium and vanadium micro-alloying, the extreme tip cold bending angle of the tested steel was between 65°-70°, which was higher than that before micro-alloying. The synergistic effect of grain refinement of NbC and precipitation strengthening of VC was the fundamental reason for the better performance of the micro-alloyed tested steel.