This paper deals with the problem of heat and mass transfer with vapor condensation in the presence of non-condensable gas outside of isothermal elliptical pipe cross-section placed in a uniform stream. The effect of its major to minor axis ratio(a/b) on the heat transfer process in the range of approaching velocity(ν) from 3 to 10 m/s and vapor mass fraction(Yv) from 0.03 to 0.3 is studied.The study reveals that the condensation heat transfer coefficient of elliptical pipe is decreased, compared with round pipe with same perimeter,for the case of a/b equal to 4.0,it decreases by 20%.The results also show that higher value of ν or Yv gives higher heat transfer rate when a/b remains constant.The effect of ratio of a/b on local heat transfer coefficient for condensation of steam around periphery of ellipse is plotted and this effect on the overall rate of heat transfer is briefly discussed.this paper aims to provide reference for the related research and application.