Abstract: Based on the theory of thin shells of revolution without moment of force,the author discusses the stress analysis and strain analysis of the semi-ellipsoidal end of a vessel in reinforced plastics,by regarding it as an orthotropic shell subjected to axisymmetric uniformly distributed loads.Combined with the practice of design,the author proposes that as a standard model of the semi-ellipsoidal ends in reinforced plastics the ratio of the major axis of the above-mentioned ellipsoid to the minor axis is (3)^1/2.