The rapid development of national defense, military industry, and aerospace puts forward higher requirements to the mechanical property, breakdown strength, dielectric properties, and heat resistance of high-performance aramid paper. However, the vast majority of aramid paper-based materials can hardly have a combination of satisfactory high mechanical properties and breakdown strength due to the porous structure of paper-based materials. Herein, we report a para-aramid chopped fibers/polyphenylene sulfide (ACFs/PPS) composite paper with a sandwich structure by designing the structure of aramid paper. Dense PPS microfiber membrane as robust armor filled and repaired the voids and defects on ACFs/PPS composite paper. Additionally, strong barrier interfaces between PPS film and ACFs/PPS composite paper effectively slow down the transmission of voltage to the inside of the composite paper. Thus we obtain the sandwich-structured ACFs/PPS composite paper with excellent mechanical strength (158.7 MPa) and breakdown strength (55 kV/mm), which are almost 1.5 and 2.5 times higher than ACFs/PPS composite paper, respectively. Besides, excellent mechanical properties and breakdown strength are wonderfully integrated with superior dielectric properties (tanδ <0.0035), chemical stability, and thermal stability (DTGmax > 575 °C), far superior to reported aramid paper-based materials. This work plays an important role in fabricating fabulous multi-attribute combinations of aramid paper-based materials and can also be extended to other materials and structures.