AlGaN quantum structure is the core of realizing high light efficiency and high stability ultraviolet(UV) solidstate light source. In recent years, great progress has been made in AlGaN based semiconductor materials and UV emission devices. However, AlGaN materials can only be grown under nonequilibrium conditions. The growth kinetics involved is very complex, which restricts the improvement of the quality of quantum wells and other structures. Because of the wide band gap, the difficulty of ptype doping and the low activation efficiency, the carrier injection is limited. The optical anisotropy is obvious, which is not conducive to light emission from the front of the device. Therefore, the performance of AlGaN based UV devices, especially in deep UV band, needs to be improved. In this paper, the relationship between AlGaN quantum structures and the efficiency of UV emission devices are summarized, and the key scientific problems and research progress in active region quantum structures, ptype doping issue of AlGaN quantum structures and optical polarization control are reviewed.