With the development of biomedical research, more advanced and comprehensive optical microscopy are required to enhance the imaging performances such as the spatial resolution, the imaging speed, the multi-dimensional information, the imaging quality, etc. Light-sheet fluorescence microscopy (LSFM), illuminating the specimen with a thin light sheet from the side and obtaining the optical sectioned image orthogonally, provides an ideal tool for long-term observation of live biological specimens due to its unique features of fast volumetric imaging speed and low photobleaching and phototoxicity to samples. In this paper, we first give an introduction to the principle and properties of LSFM. Then we address the key issues existing in LSFM and the solutions based on new principles, ideas and techniques. Some applications of LSFM in cell biology, developmental biology and neurosciences are exampled, and the development trends and prospect of LSFM are discussed. The purpose of the paper is to help researchers systematically understand the principle, the state-of-the-art techniques, and the potential applications of LSFM, and provide some references for research in this field.