A dielectric barrier discharge lamp includes a lamp tube, a discharge gas, a support member, a first electrode, and a second electrode. The lamp tube has a first and a second sealed end. The discharge gas is filled in the lamp tube. The support member is disposed at the first sealed end and extended toward the inside of the lamp tube. The support member has an accommodating space with its opening facing the inside of the lamp tube. The first electrode is disposed in the lamp tube. A first terminal of the first electrode passes through the opening of the accommodating space. A gap exists between an end of the first terminal of the first electrode and a closed end of the accommodating space. A second terminal of the first electrode penetrates and is closely fitted with the second sealed end. The second electrode is disposed outside the lamp tube.