14CO2 labeling is a method commonly used in the study of transport and distribution of photoassimilate in plant. In order to study the source-flow-sink relationship of photosynthate transport and distribution，14CO2 labeling of single leaf is required. Some of the methods of single-leaf 14CO2 labeling reported in the existing literature are complicated and some of the date are too simple，they are not practical. Therefore，through years of practice，we have established a simple and feasible method for preparing and collecting 14CO2 and feeding single leaf using the principle of the connector， which provides necessary support for the study of plant photosynthesis
