In this paper，authors have studied the growth of wild buckwheat，the change situation of the main birth time leaves chlorophyll content and every 20 days’photosynthetic rate from the seedling stage. The results show：The plant height of wild buckwheat assumes“S”curve，the number of leaves，branches，leaf area are the “single-peak”curve. Except the Fagopyrum. cymosum leaves chlorophyll content assumes“high-low”tendency， other varieties assume“low-high-low”single peak curve change tendency. F. urophyllum posses the highest photosynthetic rate average of 15.32 mg/dm2*h in the whole reproductive period and F. cymosum with an average of 8.92 mg/dm2*h is the lowest.