The effect of cross section approximation on induced stresses in pipe bends with varying ovality and thinning/thickening under internal pressure was investigated numerically. The cross sections assumed were elliptical and semi oval. FE analyses were carried out on these cross sections. The stress induced due to internal fluid pressure load was obtained at the intrados and extrados sections of the models. The effect of bend radius and the combined effect of ovality and thinning/thickening on the stress developed for these cross sections were studied and compared. The results confirm that approximation in cross section does produce considerable effect on the induced stresses. © Research India Publications.