Diffraction imaging via intensity correlation is a novel diffraction imaging method based on the high-order correlation characteristics of optical field. In this method, the Fourier diffraction spectrum information of a sample can be obtained nonlocally by calculating the correlation between the intensity fluctuation of the reference beam and the test beam. As a new imaging method, diffraction imaging via intensity correlation has the advantages of nonlocal imaging, low radiation imaging, high resolution and so on, thus it can solve problems that are difficult to handle by conventional imaging. This technology has attracted much attention recently, and has great potential in biomedicine, material science and many other fields in the future. In this paper, the latest progress of diffraction imaging via intensity correlation is briefly reviewed, and some related image reconstruction algorithms are introduced. Finally, the existing problems of this method are pointed out and its future development is prospected.