Disclosed is a preparation method for multiple precursors with concentrated particle size distribution by multistage continuous synthesis. The preparation method comprises the following steps of: 1) preparing a metal salt solution, an alkali solution and an ammonium hydroxide solution; 2) enabling a reaction kettle and a solid concentration thickener to be connected in series; 3) injecting the metal salt solution, the alkali solution and the ammonium hydroxide solution into the reaction kettle 1, wherein the slurry in the reaction kettle 1 is pumped into the thickener 1 for solid-liquid separation to increase solid content when the liquid level in the reaction kettle 1 reaches the full kettle state, and the thick slurry in the thickener 1 is pumped into a reaction kettle 2; 4) performing stirring when the reaction kettle 2 is full of the slurry, and adding the metal salt solution, the alkali solution and the ammonium hydroxide solution to continue a continuous precipitation reaction, and then overflowing the product in the reaction kettle 2 into an aging tank 1; and 5) enabling the product in the aging tank 1 to be centrifuged, washed and dried. The preparation method has the advantages that the technology is simple, easily operated, energy-saving and environment-friendly. The product features good appearance, concentrated particle size distribution, high vibration density andhigh efficiency.