A light source module includes: a convergent beam generating unit which generates, based on a pump beam emitted from a light source, a convergent pump beam having a beam size that decreases as the convergent pump beam propagates; a light guide body inside which the convergent pump beam, having been generated by the convergent beam generating unit, propagates; an extraction part which causes the convergent pump beam, having propagated inside the light guide body, to exit from the light guide body; and a wavelength conversion element which converts a wavelength of the convergent pump beam, being incident on the wavelength conversion element through the extraction part, and emits, through the light guide body, the convergent pump beam whose wavelength has been converted.