A balanced water-intake control valve includes an adjusting mechanism for the water-level between two linkage rods. The adjusting mechanism includes a first pivot guide, a second pivot guide, a lead screw and an adjusting nut. The first pivot guide is pivoted on the first linkage rod for driving a valve rod. The second pivot guide is pivoted on the second linkage rod connecting to a float body. The first and second pivot guides are connected by the lead screw at opposite ends. An adjusting nut is placed at the middle of the lead screw. By rotating the lead screw, the length between the first and second pivot guides changes. Therefore, the upper limit of the water level can be adjusted by the user after installation of the control valve.