Abstract: Aimed at the influence of temperature distribution on forming parts caused by scanning paths of filling line of electron beam selective melting technology, finite element mode with actual conditions was established and elements belonging to the rotated part were arranged in accordance with the loading sequence.Simulation results show that comparing with long-side scanning, short-side scanning and sub-area scanning, the rotated scanning of rectangular part can greatly decrease temperature gradient in the begin point and the end point of the first scanning line, especially there is a positive temperature gradient in the end point which can avoid the temperature decreasing of the molten metal.Combining rotated scanning with reversing scanning, the uniformity degree of temperature in rectangular part has greatly improved and the curl distortion caused by thermal stress has also decreased.The horizontal tensile strength of the Ti-6Al-4V tensile specimens prepared by the above optimized scanning method is 1 080 MPa.