Recently the chalcogenide semiconductors have become the subject of intense investigation for application to solar cells. In this work theoretical calculations are used to investigate the structural, optical and electronic properties of the chalcogenide compound Ag2(Sn, Si, Ge)S3 in its new structure type (P21/c). This study employs density functional theory using generalized gradient approximation (GGA) to investigate the band structure, effective mass, total and partial density of states. The calculations were also carried out using the local density approximation (LDA). Our predicted band energy gap for Ag2SnS3, Ag2SiS3 and Ag2GeS3 were \(0.408 eV\) , \(1.403 eV\) and \(1.011\) using GGA and \(0.251 eV\) , \(1.40 eV\) and \(0.822 eV\) using LDA, respectively. Optical properties such as absorption coefficient, refractive index, dielectric function, conductivity, reflectivity and loss function are plotted and discussed. These electronic and optical analysis provide insight into fundamental properties of Ag2(Sn, Si, Ge)S3 indicating its suitability for application in solar cells and optoelectronic devices.