Provided is a composite electrode for an all-solid-state secondary battery including a first active material and a second active material, wherein the first active material and the second active material include different materials from each other, and the content of the first active material is 50 vol % to 98 vol % based on the total volume of the first active material and the second active material, the first active material has a volume change rate of 0 vol % to 30 vol % according to volume expansion/contraction during a charging/discharging process, and the second active material has a volume change rate of 35 vol % to 1000 vol % according to volume expansion/contraction during a charging/discharging process.