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The design method of porous structure with minimal curved surface was introduced, and the porous TC4 titanium alloy with minimal curved surface was fabricated by electron beam 3D printing technology. The microstructure changes of as deposited and heat-treated specimens were compared and analyzed, as well as the compressive properties of the samples under different apparent densities. The research results show that using Rhino software as the main design body, and with the program algorithm of Grasshopper plug-in, the minimal surface model can be parameterized, and then the 3-matic topology optimization software can be used to carry out the surface multi-hole processing. With this method, the model of multi-stage holes with minimal surface can be established. The compressive strength of porous TC4 titanium alloy with minimal curved surface increases with the increase of apparent density. When the apparent density is 0.74 g/cm3, the compressive strength reaches 49.33 MPa. The deposited microstructure is mainly composed of β-columnar crystals, and the microstructure changes into Widmanstatten structure after annealing at 1 000 ℃ for 2 h/FC.