Jacky Martens (born 3 July 1963) is a Belgian former professional motocross racer and current race team manager.
After a steady start to the series at Hawkstone Park, Martens quickly proved himself and his machine, rising to the top of the 500cc world championship standings, with Swede Jorgen Nilsson.
The championship was contested until the very final round, where Martens clinched the title to become the first rider to win the premier 500cc class on a four-stroke since Jeff Smith accomplished the feat in 1965.
By this time, Martens was seen as something of an also-ran, but he managed to upset the form book and produce some impressive results, including a moto win at the British Grand Prix at Hawkstone Park, which was popular with Martens' large contingent of British fans.
Martens started the JM Honda Racing team to compete in the MXGP class.