Numerical results on the thermal buckling temperature of geometrically perfect HS-Graphite/Epoxy hemispherical shells with cut-out at apex subjected to uniform temperature distribution is presented. The numerical computation is based on the general shell of revolution semi-analytical finite element applicable to moderately thick shells. Studies are presented considering parameters like ratio of base radius to thickness of shell, size of the cut-out at apex and fibre orientation of the lamina and their effects are examined on the magnitude of the buckling temperature. An in-depth study on the magnitude and distribution of the total effective stress resultants and moment resultants is used to explain the role of these quantities on the magnitude of the lowest thermal buckling temperature. It is found that for a given geometry, uniform temperature rise and edge conditions the lowest buckling temperature of a hemispherical shell is mainly due to the large magnitude of the hoop stress resultant close to the edges of the hemispherical shell and also depends on the distribution of hoop stress resultants. © 2004 Elsevier Ltd. All rights reserved.