The titanium alloy samples are formed by selective laser melting (SLM) based on different scanning strategies, and the effect of scanning strategy on forming precision is analyzed. The results show that the roughness on lateral surface of forming part is strongly affected by the scanning strategy. The roughness on lateral surface of forming part by one-way scanning or Z-scanning strategies parallel to the scanning direction is better than that on the lateral surface perpendicular to the scanning direction. The degree of bending curvature of forming part by the spiral scanning strategy is relatively small and its shape structure is relatively accurate. Compared with the design model, the length and width of forming part by these three scanning strategies are reduced by 1-2 mm, while the other sizes are close. The whole forming precision of forming part by spiral scanning strategy is better than those by one-way scanning and Z-scanning strategies.