Provided is a binder composition for a solid electrolyte battery having excellent processability in solid electrolyte battery production and with which a solid electrolyte battery having excellent battery performance can be obtained. The binder composition for a solid electrolyte battery contains a particulate polymer having a core-shell structure and an organic solvent. A mass ratio of content of a polymer forming a core portion of the particulate polymer relative to content of a polymer forming a shell portion of the particulate polymer (i.e., a ratio of “polymer forming core portion/polymer forming shell portion”) is 1/0.3 to 1/5.