Doping of cations into wide bandgap semiconductors is an effective method of increasing photocatalytic activity. This work aims to find out how dopant ions like Ag+, Cu2+ and Sn2+ affect the structural, optical and photocatalytic properties of Li2GeTeO6. The parent Li2GeTeO6 (LGTO) was synthesized by conventional solid-state method, whereas the Ag+, Cu2+ and Sn2+-doped Li2GeTeO6 were prepared by a simplistic ion-exchange method. Techniques such as XRD, FT-IR, SEM-EDS, N2 adsorption-desorption analysis, UV-Vis DRS, XPS, and PL were employed to examine the physico-chemical properties of the as-prepared materials and their photocatalytic activities on the degradation of methyl violet (MV) under visible light irradiation. The acquired photocatalytic activity results revealed that all doped samples displayed enhanced photocatalytic performance compared with parent LGTO. The Ag-LGTO had the best photocatalytic activity for MV degradation, with 68.6% degradation efficiency in 180 min of irradiation. Scavenging experiments were carried out to determine the role of various active species generated on the surface of Ag-LGTO during the photocatalytic degradation of MV. The reusability and stability of Ag-LGTO up to five cycles against MV degradation were also investigated. A photocatalytic mechanism for MV degradation over the Ag-LGTO sample was also proposed based on the findings described above.