One hundred subjects were studied to throw light on the effect of smoking on serum level of alpha-1-antitrypsinandventilatory function. The results showed that there was highly significant reduction in serum level of alpha-1-antitrypsin of smokers and ex- smokers compared with non-smokers. This reduction increased with the progression of smoking index. There was marked decrease of serum level of alpha-1-antitrypsin in smokers of both cigarettes and Goza than those of either cigarettes or Goza only, but the meanserum alpha-1-antitrypsin level is nearly equal in smokers of cigarettes only and smokers of Goza only. As regard the ventilatory function, 40. 9% of smokers and 88. 9% of ex-smokers showed FVC% <80 compared with 28. 6% of non smokers. 89% of smokers and all ex-smokers had FEV1% <80 versus 28. 6% in non smokers. 85. 8% of smokers and all ex-smokers had MVV% <80 versus 47. 7% in non smokers. Also, there was prolongation of the total expiratory time in smokers and ex-smokers and strangely enough this prolongation was more in ex-smokers than smokers. The severity of the ventilatory dysfunction was inversely proportional to serum alpha-1-antitrypsin level