A target debris collection device for extreme ultraviolet (EUV) light source apparatus, includes a baffle body extending within an EUV vessel between a collector and an outlet port of the EUV vessel to allow EUV light reflected from the collector to pass through an internal transmissive region thereof, a discharge plate provided in a first end portion of the baffle body adjacent to the collector to collect the target material debris on an inner surface of the baffle body, a guide structure to guide the target material debris collected in the discharge plate to a collection tank, and a first heating member provided in the guide structure to prevent the target material debris from being solidified.