Photocatalytic degradation of organic pollutants combined with hydrogen evolution is an effective way to solve the energy crisis and environmental problems. In this work, single s-block (IA group and IIA group) and p-block (IIIA group, IVA group and VA group) metal sites are doped into monolayer GeSe for simultaneous degradation of organic pollutants and hydrogen evolution. Se-rich growth conditions are favorable for metal atoms to substitute Ge atoms. The hydrogen adsorption free energy (ΔG_H) of the Bi site on the basal planes of GeSe is −0.037 eV, which is better than those of Pt (ΔG_H = −0.08 eV), Se vacancies on the GeSe edge and S vacancies on MoS₂ (ΔG_H = −0.06 eV). Moreover, Bi doping is superior for producing ˙OH radicals. In addition, Bi doping significantly improves the infrared (IR) light absorption ability. This work confirms the critical role of s-block and p-block metal active centers for hydrogen evolution and degradation of organic pollutants in wastewater.