Provided is a binder composition for a non-aqueous secondary battery porous membrane capable of forming a porous membrane having improved adhesiveness in electrolyte solution, heat shrinkage resistance in electrolyte solution, and blocking resistance. The binder composition for a non-aqueous secondary battery porous membrane contains a particulate polymer A and a particulate polymer B having a larger volume-average particle diameter than the particulate polymer A. The particulate polymer A includes a (meth)acrylic acid alkyl ester monomer unit in a proportion of not less than 50 mass % and not more than 90 mass %. The particulate polymer B has a core-shell structure and includes a nitrile group-containing monomer unit in a core portion of the core-shell structure.