Light source module and projector

A light source module comprising:

• a light source including a light emitting element that emits a light and a substrate on which the light emitting element is mounted;
• a light guide element having an incident end on which the light emitted from the light source is incident and an emission end from which the light is emitted, and uniformizing in-plane illuminance of the light;
• and
• a holding member holding the light guide element, wherein
• the holding member is fixed to the substrate of the light source,
• the holding member has a wall portion forming a side surface surrounding the light guide element, an incident end portion facing the light source in the wall portion, and an emission end portion located at a side opposite to the incident end portion,
• the incident end portion and the emission end portion penetrate along an optical axis direction of the light, and
• the wall portion has an opening overlapping the light guide element when viewed from a direction intersecting the optical axis direction of the light.