A simulation method for visible and near infrared (VNIR) image is mentioned. The VNIR image obtained by low-level flight is adopted as data resource. After atmospheric correction, the ground reflectivity can be deducted. The simulation method consists of four steps: radiative transfer, spatial resolution, modulation transfer function, and noise simulation. The image of satellite-borne or high-level air-borne sensor could be generated by the simulation method from VNIR image. Experiment is carried out to test the method using an airship as platform. The resulting simulated image is compared to the image with quickbird panchromatic band. The result shows that simulation images enables one to effectively reproduce the entire process of remote sensing of the Earth. The method can be used to simulate VNIR image at satellite level at the same area and the same wavelength.