With the way of sand culture in pots,the paper studies the effects of different Pb2+concentrations on the contents of proline and chlorophyll in the seedlings of cucumber.The results show that : within the range of 50-500mg/L of the Pb2+concentrations,the content of the proline increases with the rise of Pb2+concentrations;within the range of 100-700mg/L of the Pb2+concentrations,the content of the chlorophyll decreases with the rise of Pb2+concentrations.