Abstract: A cold cathode fluorescent lamp (CCFL) comprises an inner fluorescent tube and an outer glass tube which is sheathed on the outside of said inner tube, characterized in that said inner fluorescent tube and said outer glass tube is separately disposed, and there is a space therebetween. Said CCFL further comprises electrodes sealed at the ends of said inner fluorescent tube and said outer glass tube. The CCFL of the present invention has a double-tube construction, as a result, the inner fluorescent tube is not so much affected by a change in the environmental temperature. Further, the inner fluorescent tube and the outer glass tube are separately disposed so that the end of the inner fluorescent tube and the end of the outer glass tube are not integrally joined, so that a rate of the breakage caused by the temperature difference between two ends is dramatically reduced.