An infrared temperature sensor that detects temperature of a detection object in a non-contact manner includes a sensor case that includes a light guiding region and a light shielded region, a film that absorbs and converts infrared rays into heat, a sensor cover, an infrared detection element, and a temperature compensation element. The sensor case includes a case base portion and a hood that surrounds the light guiding region and the light shielded region and is erected from the case base portion. The hood includes an opening part and a shielding part that protrudes toward an inside of the hood while defining the opening part and the light guiding region, and shields the light shielded region from the infrared rays. A protrusion direction of the shielding part toward the inside of the hood is adjustable.