The redesign of femoral components for total knee arthroplasty on the basis of digital 3D technology was researched and a femoral component was manufactured by Selective Laser Melting(SLM) technology to meet the demand of high suitability for the total knee arthroplasty in medicine. The 3D femoral model was extracted from the CT consecutive tomographic images of total knee on a patient. The digital 3D anatomy and measurement were performed based on the orthopedist′s operation plan, through which the current commercial component was redesigned. Then, the 3D femoral component after redesign was directly manufactured by SLM technology and the key technologies were discussed, such as process parameters, mechanical properties, spatial position optimization and manufacturing accuracy.Experimental results show that redesigning the 3D model of the femoral component is implemented according to anatomical parameters of the patient′s distal femur and the femoral component is manufactured directly by the SLM.The experiments show the manufacturing time of a single femoral component is 5.2 h, the standard deviation of manufacturing precision is 0.030 mm, and the relative density reaches 99.02%, which are all superior to those of casting standard of ASTM F75( American Society for Test Material). It concludes that the redesign and manufacturing methods based on digital 3D technology are good ways to redesign and manufacture excellent femoral components rapidly and meets the demands of the patients.