Zakkari Dempster (born 27 September 1987) was an Australian former professional racing cyclist, who competed professionally between 2006 and 2019 for the SouthAustralia.com–AIS, Drapac–Porsche Cycling, Rapha Condor–Sharp, Endura Racing, Bora–Argon 18 and Israel Cycling Academy teams. After retiring, Dempster now works as a directeur sportif for NSN Development Team, the development team for UCI WorldTeam NSN Cycling Team.

He was selected for the 2014 Tour de France finishing the race in 151st position on the general classification. Outside of cycling Dempster worked part-time as a fitness coach with Australian rules football team Carlton Football Club during the southern hemisphere summer between 2010 and 2013.