To provide electrolyte for a photoelectric transfer element improving photoelectric transfer efficiency, especially, short-circuit current density.

The electrolyte polymer additive for the dye sensitizing element is made by containing a polymer having as side chains a cation region A paired with iodide ion, a region B capable of constituting a charge-transfer complex together with iodine, and a coupling region C with the number of carbons of two or more directly coupling the A and the B. The electrolyte for the dye sensitizing photoelectric transfer element contains 0.1 to 50 wt.% of the polymer additive, 99.8 to 49.9% of an organic molten salt compound, and 0.1 to 10 wt.% of iodine.