Lanthanide metal-organic framework (Ln-MOF) is a novel inorganic-organic porous material, which is composed of organic ligands and lanthanide metal ions or metal clusters. Ln-MOFs have abundant molecular building blocks and a high fluorescence quantum efficiency due to the high coordination number and unique optical properties of lanthanide metal ions. This review summarized recent work on Ln-MOFs, mainly focusing on the application of Ln-MOFs in photonics such as temperature detection, small molecule detection, gas detection, etc. The design and controllable preparation methods of Ln-MOFs as well as the assembly of organic dyes, perovskite quantum dots, etc. in the Ln-MOFs channel and the assembly of Ln3+ in the MOFs channel were introduced. In addition, the future development and application prospects of the Ln-MOFs were also proposed.