A clamp structure of an external electrode lamp includes a first fixing device, a second fixing device, and a metal strip. The first fixing device has a first indentation and the second fixing device has a second indentation for clamping an electrode of the external electrode lamp. In addition, the metal strip is located between the first and second fixing devices to contact the electrode of the external electrode lamp for providing power. The electrode can be further equipped with a cushion for fixing the electrode onto the first and second fixing devices.