Description of the data and file structure This data was collected to study the effects of heat stress during ear peep in wheat genotypes with contrasting heat tolerance (Tolerant: RAJ3765, HD2932 and Susceptible: HD2329, HD2733) on physiology, yield and yield components, and proteomics of flag leaves and spike tissues. The figures, tables, and supplementary figures in this study were prepared using the data provided in the supplementary tables. The supplementary data Supplementary Table S1-S10.xlsx Supplementary Figures S1-S6 and Methods.pdf Other publicly accessible locations of the data: All mass spectrometry proteomics data has been deposited into the ProteomeXchange Consortium via the PRIDE. The dataset is available via ProteomeXchange with the identifier PXD048499.