In this study, sulfamic acid-functionalized Fe3O4 nanoparticles (Fe3O4@EDA-SO3H) was successfully synthesized as an effective nanomagnetic acid catalyst. This magnetically recoverable catalyst was well characterized by FT-IR, XRD, TGA, VSM, SEM, EDX and CHN techniques. The prepared catalyst exhibited high e¨ciency in the synthesis of quinoxaline, benzothiazole and benzoxazole derivatives via simple and environmentally-benign procedure. The catalyst can be readily separated from the reaction medium by employing an external magnet and reused several times without signi¦cant loss of its catalytic activity.