How small can computers be in the future? Can you imagine how molecular machines works? At present, traditional electronic devices based on semiconductor materials will face severe challenges. These challenges are not only technical and technological limitations, but also, more importantly, theoretical limitations. With the rapid development of nanotechnology and in-depth research, great progress has been made in the theory and practice of molecular electronic devices in recent years Molecular electronic devices use molecules (including biomolecules) with certain structures and functions to build an ordered system in the molecular scale or supramolecular scale. They make use of the quantum effect of electrons to work, control the behavior of single electrons, and realize the functions of information detection, processing, transmission, and storage, such as molecular diodes, molecular memories, molecular wires, molecular field effect transistors, and molecular switches. As a stable quantum system with abundant photoelectric properties, molecules have many electronic transport properties different from semiconductor devices. Molecular electronic devices have the following advantages: (1) small molecular volume, which can improve the integration and operation speed; (2) selecting appropriate components and structures can widely change the electrical properties of molecules; (3) molecules are easy to synthesize, and the required structure can be formed by a self-assembly method; and (4) the molecular scale is on the nanometer scale and has advantages in cost, efficiency, and power consumption. With the traditional silicon-based electronic devices becoming smaller and smaller, the impact of quantum effects is gradually recognized. The research on molecular electronics has made significant breakthroughs. As more and more excellent characteristics such as potential thermoelectric effects, new thermally induced spin transport phenomena, and negative differential resistance are discovered and understood, it is believed that “smaller,” “faster” and “cooler” high-tech products will eventually be realized in the future. However, at present, all research work on molecular devices is still theoretical, and there is still much work to be done in terms of device manufacturing reliability, experimental repeatability, and manufacturing cost. Therefore, the purpose of this review is to attract more experts, scholars, and engineers from different fields such as chemistry, physics and microelectronics to participate in this research, so that molecular electronic devices can become a reality as soon as possible. Reference: “Single Molecule-Based Electronic Devices: A Review” by Bingrun Chen and Ke Xu, 8 October 2019, NANO.DOI: 10.1142/S179329201930007X This work was supported by the National Nature Science Foundation of China (Grant Nos. 11704263). The corresponding author for this study is Bingrun Chen. Ke Xu from Shenyang Jianzhu University is a co-author.