Provided are a binder composition for a secondary battery, that contains a metal element-containing component having a particle diameter of 10 μm or less and a binder composed of a polymer containing less than 30% by mass of a constitutional component derived from an ethylenically unsaturated carboxylic acid in all the constitutional components of the polymer, in which the content of the metal element-containing component is 1.0×10−3 to 1.0×104 ppm; a solid electrolyte-containing composition for a secondary battery, which contains the binder composition and an inorganic solid electrolyte, in which the content of the metal element-containing component is in a specific range; a sheet for an all-solid state secondary battery, which has a layer formed of the composition; and an all-solid state secondary battery.