To study changing characteristics of chlorophyll SPAD value in leaves during their developments and the difference of agronomic traits and economic traits in different flue-cured tobacco cultivars,field experiment was conducted to investigate chlorophyll content in leaves of flue-cured tobacco with four cultivars (K326,HD,NC82,Liaoyan13) by SPAD-502 chlorophyll meter,periodically.The results showed that changing characteristics of both chlorophyll SPAD value and relative variance rate involved not only the cultivars,but also the leaf positions.