Diverse factors constrain the potential to grow wheat in many parts of the world. Heat and drouhgt stress, which have been discussed in this work, belong to important abiotic stress factors. The key solution for stabilizing and increasing yield under suboptimal environmental conditions is to breed stress adapted varieties. However, before genetic variability for successful breeding purposes can be used, the understanding of physiological and morphological adaptation processes is necessary. At present there are no clear criteria to be used in breeding heat and drouhgt tolerant varieties. The objective of this work is: (i) to test different spring wheat varieties for their yield performance under heat and drought conditions in comparison to control conditions. (ii) to find traits which characterise heat and drought tolerance of spring wheat genotypes and permit a selection on a large scale in early stages of development. For that purpose spring wheat genotypes of different origin were examined under heat and drouhgt stress in the field and in growth chambers for yield and yield components as well as for different physiological parameters.