A fixing device to fix an image formed on a recording material to the recording material includes a cylindrical belt, a nip portion forming member contacting the belt, a backup member forming a nip portion with the nip portion forming member, a halogen heater including a bulb filled with gas and having a sealing portion sealing the bulb, and a reflection member that is long in a longitudinal direction of the halogen heater, wherein an image formed on the recording material is fixed to the recording material at the nip portion, and wherein the reflection member has a length greater than a length of a light emission area of the halogen heater, and the nip portion forming member has a length greater than the length of the reflection member.