Embodiments of the present invention provide a projection correction method and device. The method comprises: obtaining the distance DMN between marking points M and N preset on a projection device; obtaining the distances DM and DN from M and N to a projection background along a preset direction; according to DMN and a difference between DM and DN, determining a relative included angle αx between an end face where a projection lens is located and a plane where the projection background is located; obtaining a first correction parameter corresponding to the relative included angle αx according to the relative included angle αx and a preset correspondence between relative included angles and correction parameters; and correcting a projection region of the projection device on the projection background according to the first correction parameter. When projection correction is performed by using a solution provided in the embodiments of the present invention, it is not required to perform correction according to the image processing result of an image of a projection background; instead, correction can be performed according to the data processing result of the distances from preset marking points to the projection background, thereby reducing time spent in data processing during the projection correction, and improving the processing speed.