Abstract:The present paper compared winter wheat (Triticum sativum L.c.v. "Feng-mai-13") grown on the different altitude. The results showed, comparing wheat grown on higher altitude (2150 m) with that grown on lower altitude (840 m), that the former has a longer duration of leaves, a smaller area per leaf and total leaf area a plant; a lower intensity of photosynthesis during early stage, a higher intensity of photosynthesis during filling period, and little difference between both stages; a heavier thousand-kernel-weight, and a lesser number of grains per head than the latter. On the other hand, the difference of yield component has been disscused in terms of photosynthesis-yield. We proposed, on tbe basis of the dis- scusion, an assumption that how increase in number of grains per head which wheat is grown on higher altitude.