This paper presents a study of the relationship between cutting force and tool crater wear of solid carbide tool during milling Ti6Al4V. The cutting force model in milling considering tool crater wear is discussed, which shows that for given the cutting conditions, tool geometries, and workpiece material, cutting force under the tool crater wear effect could be predicted easily and conveniently. The tool wear condition in milling Ti6Al4V is obtained by finite element simulation method. In addition, the experimental work of end milling Ti6Al4V with solid carbide tool is developed. Comparisons among experiment results, mathematical model results, and finite element simulation model results, including cutting force and tool wear, are discussed. The results show that the proposed mathematical model could predict cutting force under the tool crater wear effect with higher accuracy.