van der Waals heterostructures (vdWHs) have been widely studied due to their particular properties. In this work, the electronic structure and the optical properties of MoSSe/InSe vdWH are studied by first-principles calculations, and the changes of strain modulation properties are also discussed. Theoretical research shows that the MoSSe/InSe vdWHs have an indirect band gap and the band alignments are type-I and type-II correspond to two different stacking patterns, respectively. Compared with MoSSe and InSe monolayer, the optical absorption of the MoSSe/InSe vdWH in the visible and ultraviolet region is improved. In addition, the band gap, the band alignment, and the optical absorption of the MoSSe/InSe vdWH can be effectively modulated by biaxial strain. This work provides possibilities for the application of the MoSSe/InSe vdWH in optical devices, electronic devices and photocatalysis.

范德华异质结构（vdWHs）由于其特殊的性能而被广泛研究。在这项工作中，通过第一性原理研究了MoSSe / InSe vdWH的电子结构和光学性质，并讨论了应变调制性质的变化。理论研究表明，MoSSe / InSe vdWHs具有间接带隙，能带排列的I型和II型分别对应于两种不同的堆叠模式。与MoSSe和InSe单层相比，MoSSe / InSe vdWH在可见光和紫外光区域的光吸收得到了改善。另外，MoSSe / InSe vdWH的带隙，带取向和光吸收可以通过双轴应变有效地调节。