Terahertz(THz) Quantum Cascade Lasers(QCLs) are semiconductor devices based on intersubband electron leaps, which are characterized by small size, lightweight, easy integration, tunable frequency and high energy conversion efficiency, and have become one of the hotspots of current research. At present, THz QCLs have not appeared high-performance devices, and electron transport, as the most basic and fundamental starting point of THz QCLs, is an important way to break through this bottleneck. In this paper, the research progress in electron transport for THz QCLs is sorted out. Firstly, the influence of various scattering on the performance of THz QCLs is discussed. Secondly, the method to improve the operating temperature of QCLs through the optimized design of active region is also introduced. Finally, the research on electron transport of THz QCLs is outlooked. This work shows certain reference significance for improving the performance and application of THz QCLs.