Jesus, starting a league game for the first time since returning from a knee injury last month, converted a 35th-minute penalty after being clipped in the box by Luke Ayling.
Ben White doubled Arsenal's advantage from Gabriel Martinelli's pass before Brazilian Jesus, signed from Manchester City last summer, struck again from close range in the 55th minute from Leandro Trossard's assist.
Leeds had troubled Arsenal in the opening period but once Jesus put the hosts ahead it was relatively plain sailing as they restored their eight-point lead over champions Man City.
The most important thing is that everyone that has come in has played good," Jesus said.
His persistence and trickery earned Arsenal a nerve-settling penalty on Saturday as he jinked into the box and Ayling, rather unluckily, conceded the spot kick as Jesus tumbled.