The synthetic metjods for high yield og multiwalled carbon nanotube and siglewalles carbon nanotube with high purity by are discharge have been investigated. MWNTs were synthesized under different pressure of helium and the gas mixture of argonad and hydrogen. Relatively high pressure of 300-400 torr was required for SWNTa. The introductiom of hydrogen gases during the synthesis of MWNTs improxed the yield and purity of the samples.