Optical waves as information carriers can process two-dimensional information in parallel with high speed and have many degrees of freedom (e.g., wavelength, amplitude, phase, and polarization). Therefore, optical encryption technologies and optical cryptosystems demonstrate great potential for applications. With the rapid growth of encrypted data transmission volume, it becomes increasingly important to realize information compression while encrypting because it shortens the time required to process these data and substantially saves storage space. In this paper, we propose the concept of generalized optical image compression-encryption and categorize its compression strategies into three types, including plaintext, ciphertext, and synchronous compressions. On this basis, the specific compression methods suitable for each strategy are specified, and the research progress of optical image compression-encryption is introduced by describing the applications of these compression methods at some instances. Moreover, the potential future research directions of optical image compression-encryption are also presented.