<p>The CO₂ and water vapor exchange of leaves is regulated by stomata. To date, stomatal traits and gas exchange parameters during plant evolution and domestication remain unclear. Here, we created a database including 337 observations of stomatal traits and gas exchange parameters in C₃ species, ranging from ferns to angiosperms. The results showed that the light-saturated photosynthetic rate (<i>A</i>_sat) dramatically increased from ferns and gymnosperms to non-crop angiosperms and further increased to crops. The improvement of <i>A</i>_sat along phylogeny was related to the increments of mesophyll conductance, which was mainly regulated by stomatal anatomy (stomatal traits). In different groups of angiosperms, woody plants had lower <i>A</i>_sat and stomatal conductance (<i>g</i>_s) and larger stomatal size (SS) than herbs. <i>A</i>_sat in deciduous angiosperm trees was significantly higher than that in evergreen angiosperm trees. The stomatal density (SD), stomatal pore index (SPI), <i>A</i>_sat and <i>g</i>_s in annual herbs were higher than those in perennial herbs. The improvement of <i>A</i>_sat and <i>g</i>_s in crops was mainly related to the increments of SD. Our results suggested that the improvement in photosynthesis of plants during plant evolution and domestication is related to the increase in SD and to the decrease in SS.</p>