In this study, the AISI 316L stainless steel samples produced by the laser-based powder bed fusion (LPBF) process were subjected to annealing at temperatures of 900°C, 1000°C, and 1100°C for holding times up to 6h. The impact of annealing treatment on the evolution of microstructure, hardness, and anisotropy in different planes of the samples was systematically investigated. The findings revealed that after annealing at 900°C for 3h, melt pool boundaries remained visible, indicating incomplete diffusion under these conditions. However, at constant temperature increasing the annealing duration to 4h, resulted in the disappearing of melt pool boundaries, and reducing the average hardness values from 256, 271, 242 HV0.2 to 195, 198, and 205 HV0.2 in TD-ND, TD-BD, and BD-ND planes, respectively. The same behavior was also achieved by annealing at higher temperatures of 1000°C and 1100°C. In addition, by increasing the holding time over 4h, the average hardness raised slowly for all samples, which may be related to the accumulation of carbide particles at grains and grain boundaries that restricts the grain boundary motion. Furthermore, increasing the annealing temperature to 1000°C and 1100°C for 4h led to the formation of annealing twins and complete transformation of columnar grains into equiaxed grains, as observed in the microstructure. A comparison of the microstructure and hardness values (186-188HV0.2) confirmed that full recrystallization and the elimination of anisotropy were achieved after annealing at 1100°C for 4h due to the formation of new recrystallized grains, annihilation of cell structures and complete dissolution of melt pool boundaries.