On his way to a second straight victory this season, Marquez beat one of his main rivals for the title, Italy's Andrea Dovizioso (Ducati Desmosedici), who crashed in the 18th lap along with his teammate Jorge Lorenzo and Dani Pedrosa (Repsol Honda), both of Spain, reports Efe.
Marquez leads the MotoGP World Standings with 70 points, 12 ahead of France's Johann Zarco (Yamaha), who also came second at Jerez, and 20 points ahead of Spain's Maverick Viñales (Yamaha) in third overall.
Lorenzo had a perfect start, moving from fourth to lead the race ahead of Cal Crutchlow, who had clinched the pole position, Pedrosa and Zarco.
Marquez, last season's defending champion, started the race from the fifth spot, and waited for his chance to overtake Crutchlow and Zarco, among others.
In early stages, the race lost one of the title contenders, Spain's Aleix Espargaro, with a technical problem.
Marquez took advantage of Lorenzo's tire strategy to pass him, and steadily built up his lead over his nearest rivals.
Dovizioso's crash came after his successful takeover attempt against Lorenzo, as Pedrosa tried to take advantage of the situation, leading to the collision involving all three.