A joined body includes: an adherend; a primer layer provided on the adherend; and a pressure-sensitive adhesive layer provided on the primer layer. The primer layer contains, as an effective component, at least one of chlorinated polypropylene and chlorinated polyethylene and an amount of the effective component per unit area is 0.5 [mg/cm2] or less. The surface of the adherend may be formed of at least one of polypropylene (PP), polyvinyl chloride (PVC), and ethylene-propylene-diene rubber (EPDM).