A generalized isovector formalism is used to derive the isovectors and isogroup of the self-dual Yang–Mills (SDYM) equation in the so-called J formulation. In particular, the infinitesimal ‘‘hidden symmetry’’ transformation, a linear system, and a well-known Bäcklund transformation of the SDYM equation are derived in the process. Thus symmetry and integrability aspects of the SDYM system appear in natural relationship to each other within the framework of the isovector approach.