An electrical storage device electrode binder composition exhibits an excellent binding capability, and makes it possible to produce an electrical storage device electrode that exhibits excellent charge-discharge durability characteristics. The electrical storage device electrode binder composition includes a polymer (A) and a liquid medium (B), wherein the polymer (A) is polymer particles, and the ratio (DA/DB) of the average particle size (DA) of the polymer particles measured by using a dynamic light scattering method to the average particle size (DB) of the polymer particles measured by TEM observation is 2 to 10.