A takedown utility cart includes rectangular platforms each having four corners, each platform including a main panel having four beams; four sets of post sections, each set secured through one corners of the platforms; two side walls each threadedly fastened between sides of two adjacent platforms; a rear panel having two sides threadedly secured to rear ends of the side walls respectively so that an open space is defined by the platforms, the side walls, and the rear panel; at least one drawer retractably mounted in the space; and a lock assembly mounted on the rear panel for locking or unlocking the drawer.