Magnesium alloy has good biocompatibility, biodegradability, density and elastic modulus similar to human bone, so it has broad application prospects in the biomedical field. Additive manufacturing technology provides an effective way to produce magnesium alloy porous structure implants with complex shapes. However, the characteristics of magnesium alloy, such as low melting point and easy gasification, bring great difficulties to additive manufacturing. The forming quality of three - period minimal curved surface structure (TPMS) of WE43 magnesium alloy made by Laser powder bed fusion (LPBF) additive was studied from two aspects of design method and process. The influences of different TPMS structure and LPBF process parameters on porosity and forming accuracy were analyzed. The compressive mechanical properties of TPMS structure were further tested. The in vitro degradation performance of TPMS porous structure was studied. The relationship between TPMS structure type, forming quality and compressive mechanical properties was obtained, and the effect of TPMS structure type on the degradation rate in vitro was analyzed. The results show that the TPMS structure has better forming quality and compressive mechanical properties than the sheet TPMS structure with the same design porosity, and the sheet TPMS structure has stronger ability to withstand large deformation than the network TPMS structure. The degradation rate of TPMS structures increases first and then decreased. The structural integrity of porous structures of TPMS was lost at 12 h, and the degradation rate is positively correlated with the actual porosity.