This article describes how RNA expression data of 173 genes were produced on 384 sunflower hybrids grown in field conditions. Sunflower hybrids were selected to represent genetic diversity within cultivated sunflower. The RNA was extracted from mature leaves at one time 7 days after anthesis. These data allow to differentiate the different genotype behaviours and constitute a valuable resource to the community to study the adaptation of crops to field conditions and the molecular basis of heterosis.