Abstract: Ghost imaging is a non-local imaging method. Compared with traditional imaging, it has stronger ability to resist environmental interference, but it has the problems such as too many measurement times needed and low image quality. In this paper, a correlation imaging scheme based on orthogonal speckle is proposed which uses discrete cosine speckle to illuminate the object and compressed sensing algorithm to obtain the image of the object. The results show that the scheme can effectively improve the image quality, and the number of measurements is less. The scheme is essentially based on the prior information of the object to select the speckle of the irradiated object. It is an optimization method for speckle. It has the advantages of simple operation and remarkable effect, and can promote the practical development of correlation imaging in the future. This method may be applied in the fields of 3D imaging, radar imaging and optical encryption based on correlation imaging.