The 2019 Micro-Nano Optoelectronics Summit Forum was successfully held on November 13, 2019 in Wuhan Optical Expo. The forum was co-sponsored by the International Nano-optoelectronics Research Center of Tsinghua University, Chinese Laser Press and OE Show. It was initiated and chaired by Professor Yidong Huang, director of Department of Electronic Engineering, Tsinghua University. The forum attracted more than 200 researchers, industry representatives and students in the field of micro-nano optoelectronics. Professor Yidong Huang of Tsinghua University presided over the forum and delivered the opening speech. Professor Yu Yu of Huazhong University of Science and Technology, Professor Wei Jiang of Nanjing University, Associate Professor Kaiyu Cui of Tsinghua University, and Professor Xinlun Cai of Sun Yat-Sen University took invited talks on silicon-based photonic integration, silicon optical waveguide integration, optomechanical crystal nano-cavities and lithium niobate modulator, respectively.