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The effect of solution treatment on the microstructure of Mg-Zn-Gf-Y-Zr alloy was studied by OM, SEM and TEM, and the corrosion resistance and mechanical properties of the alloy were tested. The results show that the solution treatment can effectively improve the inhomogeneity structure of the as-cast alloy. The grain size of the alloy increases with the increase of solution treatment temperature in the range of 460-510 ℃, and the second phase dissolves and tends to be spherical. When the solution temperature is greater than 490 ℃, a small amount of Zn₂Zr₃ phase is precipitated and the precipitation phase tends to increase and coarsening with the increase of temperature. The T4-490 sample exhibits uniform microstructure, good corrosion resistance and mechanical properties. The corrosion rate of the weight loss test is 0.472±0.048mm /a, and the tensile strength, yield strength and elongation were 196.2±3.5 MPa, 111.1±6.4 MPa and 18.9±1.3%, respectively. The tensile properties of T4-490 sample after immersed in SBF decreased sharply within 1-7 days, and decreased more slowly within 7-14 days. With the extension of soaking time, the fracture form changes from quasi cleavage fracture to brittle fracture.