Abstract: A preparation method of an indium phosphide quantum dot (InP QD) with a large Stokes shift includes: fully dissolving the indium precursor at a first temperature under isolation from oxygen and water, adding a phosphorus precursor, and heating to a second temperature to allow a reaction to obtain an indium phosphide (InP) core; adding a shell precursor to the InP core, and heating to a third temperature to obtain QD with a core-shell structure; and adding anionic and cationic precursors successively to the QD with the core-shell structure at the third temperature to obtain the InP QD with an emission peak adjustable in a range of 465 nm to 650 nm, a high quantum efficiency, and a large Stokes shift. The InP QD mainly has a large Stokes shift to inhibit self-absorption and non-radiative resonance energy transfer.