Ag-based electric contact materials (ECMs) critically determine the performance of low-voltage switchgear for low-frequency and high-current control. However, these materials suffer from poor environmental friendliness, low tensile strength (< 200 MPa), high material loss (> 5%), and short service life (< 1 × 10⁴ cyc). To improve the comprehensive performance of Ag/Ti₃AlC₂ ECMs, this study designs a reinforcing phase with a novel composition and structure. For electrical contacting processes, the layered structure of MAX phases and their excellent wettability with metals ensure strong anti-material transfer performance of Ag/MAX composites. However, the interdiffusion between the A-layer atoms of MAX phases and the Ag matrix leads to interfacial solid-solution behavior that deteriorates the electrical conductivity and electrical contact reliability. To create an innovative design of the morphology and structure of MAX phases, this study combines mechanical ball milling, spray granulation, and vacuum heat treatment to prepare large-sized spherical Ti₃AlC₂-reinforcing phase powders with surface-loaded nano-Al₂O₃ particles that are subsequently combined with the Ag matrix. The spherical micro- and nano-composite structured reinforcing phase is found to improve the microstructure uniformity of the Ag/Ti₃AlC₂ material, promote unidirectional diffusion of Ag along the grain boundaries of the spherical reinforcing phase into its interior, and restrict the Ag-Al interdiffusion behavior within the reinforcing phase. Consequently, the resistivity reduced from 5.462 to 4.431 μΩ·cm. The nano-Al₂O₃ particles on the surface of the spherical reinforcing phase are mainly distributed at the Ag/Ti₃AlC₂ interface; however, some are detached and dispersed through the matrix. The unidirectional Ag diffusion and distribution of nano-Al₂O₃ particles collectively enhance the bonding quality of the composite interface, thereby increasing the tensile strength (228.8 MPa), interface surface hardness (140.2 HV), and interfacial nanohardness (3.261 GPa). During 2 × 10⁴ cyc of arc discharging, the microsized spherical Ti₃AlC₂ reinforcing phase and nanosized Al₂O₃ particles synergistically increase the viscosity of the molten pool at high temperatures caused by electric arc discharging, effectively restricting the movement of liquid Ag, diminishing the material loss to 1.7%, and thus improving the antiarc erosion performance of Ag/Ti₃AlC₂ composites. This work provides research ideas and technical references for the performance improvement of Ag-based ECMs.