The lithium dendrite growth is still a serious challenge and impeding the realistic applications of all-solid-state lithium batteries. In view of the amide containing sediment layer can be stable on lithium/cathodes, a composite polymer electrolyte with amide-based matrix is in-situ built on porous electrodes. With the introduction of amide, the polymer electrolyte presents excellent ability to inhibit lithium dendrite growth and makes the Li/Li symmetric battery stably work for 500 h with a good ionic conductivity of 4.25 × 10⁻⁵ S/cm at 40 °C. The solid electrolyte also shows a wide electrochemical stable window and good interface contact with the porous cathode. Utilizing this composite polymer electrolyte, the all-solid-state Li/LiFePO₄ battery shows an initial discharge capacity of 146.5 mAh/g at 0.1 C under 40 ^oC and remains 81.4% in 100 cycles. The polymer electrolyte also can present better properties after modification. These results demonstrate that the presented PA-based composite polymer electrolyte could be served as a good electrolyte candidate for all-solid-state lithium-ion batteries.