This composition for a secondary battery electrode mixture layer contains a binder, an active material, and water. The binder contains a first cross-linked polymer and a second cross-linked polymer. The first cross-linked polymer includes a carboxyl group and a 1-mass% concentration aqueous solution of said polymer exhibits a viscosity of less than 10,000 mPa·s. The second cross-linked polymer includes a carboxyl group and a 1-mass% concentration aqueous solution of said polymer exhibits a viscosity of 10,000 mPa·s or higher. The used amount of the second cross-linked polymer is 0.1-55 mass% of the total amount of the first cross-linked polymer and the second cross-linked polymer.