In this paper, the first-principles method based on density functional theory was used to study the electronic structure and optical properties of germanene at different warpage, and the influence of warpage on electronic structure and optical properties was analyzed. Six different approximation methods were used to optimize the geometric structure of germanene, and the most stable structure system was obtained. On this basis, different warping structures were selected, and the stability of warping degree was demonstrated, and three stable warping structures were obtained. The band gap of germanene is opened by adjusting the warping degree, and the conversion between indirect band gap and direct band gap is realized by adjusting the warpage. The regulation mechanism of band structure and the effect of warpage on the optical properties of germanene are explained by analyzing the density of states. The results show that the warpage can effectively regulate the electronic structure and optical properties of germanene, and improve the photoelectron utilization efficiency.