A composition for an electrochemical device, the composition containing a single-walled carbon nanotube, a binder and a solvent. The binder contains a fluorine-containing copolymer containing a vinylidene fluoride unit and a fluorinated monomer unit other than the vinylidene fluoride unit, and the content of the vinylidene fluoride unit in the fluorine-containing copolymer is 50.0 mol % or more relative to total monomer units. Also disclosed is a positive electrode mixture including the composition and a positive electrode structure including a current collector and the positive electrode mixture layer provided on one or both sides of the current collector.