The work aims to explore the ideal solution treatment regimens of Inconel 718 alloy produced via laser additive manufacturing technology. Inconel 718 alloy was prepared by laser additive manufacturing technology and the effect of different solid solution temperature on the microstructure, precipitation phases and hardness of as-deposited Inconel 718 were investigated by microstructure observation (optical microscope and scanning electron microscope), energy spectrum analysis and Vickers hardness test. The solution temperature had a significant effect on the grain size of as-deposited Inconel 718. When the solid so-lution temperature was 1000 ℃, recrystallization occurred on the as-deposited coating after holding for 1 h. When the solution temperature increased to 1080 ℃, the grain size was refined compared with the as-deposited microstructure, and the recrystalli-zation process was completed. In addition, the precipitation and dissolution behavior of as-deposited Inconel 718 was also different under different solution temperature. When the solution temperature was 940 ℃, there were some obvious δ phases around the Laves phase. However, when the solution temperature continued to increase, the content of δ phase decreased significantly due to solution treatment. Also, the microhardness of the alloy was related to the solution temperature. When the solid solution temperature was 940 ℃, the hardness of the alloy was higher than that of the as-deposited Inconel 718. However, with the increase of the solid solution temperature, the hardness of the alloy began to decrease rapidly which was lower than that of the as-deposited one, and kepts table when the temperature was 1050 ℃. However, when the temperature was over 1150 ℃, the microhardness continued to drop rapidly. The heat treatment regimens of as-deposited Inconel 718 alloy is different from that of the conventional cast and wrought alloy. The ideal solution temperature of as-deposited Inconel 718 alloy is between 1080 ℃ and 1150 ℃ for one hour.