A composite particle for an electrochemical element including an electrode active material and a granular polymer, wherein the granular polymer is composed of a graft polymer, the graft polymer has a molecular structure which includes a specific backbone portion and a graft portion bonded to the backbone portion, the graft portion being a hydrophilic graft chain, a content ratio of the graft portion in the graft polymer is 1 part by weight or more and 40 parts by weight or less relative to 100 parts by weight of the backbone portion, and an angle of repose of the composite particle is 20° to 40°. Also provided are a producing method of the composite particle, an electrode for an electrochemical element including the composite particle, and an electrochemical element including the same.