The object of the present invention is to provide an electrolyte for a fluoride ion battery with high activity for fluoridating an active material. The present invention solves the problem by providing an electrolyte for a fluoride ion battery comprising a fluoride complex salt as at least one of LiPF6 and LiBF4, and an organic solvent; and B/A is 0.125 or more in the case where a substance amount of the organic solvent is regarded as A (mol) and a substance amount of the fluoride complex salt is regarded as B (mol).