This paper describes influence of flame stretch (especially curvature) on flame structure of triple flames. In front of the triple point, the stoichiometric mixture is formed. However, it has been indicated that the flame structure is different from the stoichiometric laminar premixed flames. In this study, we compare the flame structure of curved premixed flames with triple flames. As a result, the maximum heat release rate for triple point is smaller than that for unstreched laminar premixed flames, and it is also smaller than maximum heat release rate for curved premixed flames.