The laser of 2 μm waveband has attracted considerable interests as mid-IR light source, due to their extensive applications in laser medicine, environmental monitoring, laser lidar, remote sensing and laser ranging. Tm,Ho:YAlO3 crystal with good mechanical and thermal properties has achieved multifold continuous and pulsed mode of 2 μm waveband lasers. The research and development on Tm,Ho:YAlO3 laser at 2 μm waveband are classified and summarized, which include the techniques of continuous-wave and pulsed mode for Tm/Ho doped YAlO3 and Tm, Ho:YALO3 laser output, and the latest development of high power Tm,Ho:YAlO3 laser. The main techniques include active Q-switch, passive Q-switch and Ho laser pumped by Tm laser. The prospect and applications of Tm,Ho:YAlO3 laser are discussed in the article.