Multiwalled carbon nanotubes (MWCNTs) doped wilh heleroatoms are promising materials for severalel eclronic applications. This work synthesized the doped MWCNTs using ane lectric arc discharge technique and studied their eleclrical and field emission properties. Owing 10 their improved electrical properties such as work function, carrier concentration and electrical conductivity, the doped MWCNT emitters show improvd field emission characteristics. Oxidation rrsistance of the doped MWCNTs is enhanced up 13% as well, probably causing a higher emission current and a longer emission stability. Aspect ratios of MWCNTs, which are length-Io-diamelerr atios, are increased by doping MWCNTs, affecting the field enhancement faclors of CNT emitters. These highly conductive and thermally stable doped CNTs seem to be promising as an excellent emitter material for cold mission guns which can be widely applied to x-ray tubes, UV-Iamps, and othere lectron beam treatments.