The purpose of this paper is to investigate the optimal condition of the Syngas production by reforming of fuel using plasmatron. Plasma was generated by air and arc discharge. The effects of applied steam, $CO_2$ or Ni-catalyst on fuel conversion, as well as hydrogen yield and $H_2$/CO ratio were studied. When the variations of $O_2$/fuel ratio, $H_2O$/fuel flow ratio and $CO_2$/fuel flow ratio were $0.94{sim}1.48$, $4.3{sim}10$ and $0.8{sim}3.05$, respectively. Under the condition mentioned above, result of $H_2O$/fuel flow ratio was maximum $H_2$ concentration, or $28.2{sim}31.6%$, and result of $H_2O$/fuel flow ratio with catalyst was minimum CO concentration or $6.6{sim}7.1%$. and $H_2$/CO ratio were $3.89{sim}4.86$.