Bryan Malcolm Gaensler (born 1973) is an Australian astronomer based at the University of Toronto. He studies magnetars, supernova remnants, and magnetic fields. In 2014, he was appointed as Director of the Dunlap Institute for Astronomy & Astrophysics at the University of Toronto, after James R. Graham's departure. He is currently the co-chair of the Canadian 2020 Long Range Plan Committee with Pauline Barmby.