The invention provides a method for preparing a semiconductor material on insulator by low-dose injection. The method comprises steps: 1) carrying out epitaxy on a doped monocrystal thin film on the surface of a first substrate; 2) carrying out epitaxy on a top layer semiconductor material; 3) depositing an insulating layer; 4) injecting stripped ions to preset depth positions of the first substrate under the monocrystal thin film from the surface of the insulating layer; 5) providing a second substrate, and bonding the second substrate and the insulating layer; 6) and performing annealing treatment, so the monocrystal thin film absorbs the stripped ions, and finally the first substrate and the top layer semiconductor material separate from the monocrystal thin film. Through controlling ion doping of the ultrathin monocrystal thin film, adsorption of injected ions is controlled, and intelligent stripping can be realized by low-dose injection. Stripping cracks are on the ultrathin layer, and the cracks are very small, so that a high quality semiconductor material on insulator can be obtained.