Abstract: The hot ductility of the V-containing micro-alloying steel CC (continuous casting) slabs and precipitation of vanadium carbide in the tensile specimens were investigated. There sults indicate that the precipitation ratio and precipitation rate of vanadium in the specimens reach maximum respectively at 900, -825 and 825℃. There is still l0%-l7% of vanadium precipitated when the deformation temperature decreases to 800-700℃. Vanadium largely affects the ductility of the steel in the low ductility temperature Region III. Embrittlement of steel with higher V content is severer in the region and the embrittlement extends to lower temperature.