Manganese is an important mineral resource in Zunyi. After mining, it will have a series of environmental effects on the mining area. Based on the principle of ecology, invasive plants are used as pioneer plants to explore the recovery of the mining area. The physiological response of invasive plant Conyza canadensis under manganese stress of 0.50%, 1.00%, 1.50% and 2.00% were studied in this paper. The results showed that the content of proline and soluble sugar in the leaves of Conyza canadensis showed an increasing trend at concentrations of 0.50%, 1.00%,1.50% and 2.00%. The results of soluble sugar, malondialdehyde（MDA） and proline in the leaves of Conyza canadensis were not significantly different in the manganese chloride treatment group with 0.50% and 1.00%, but significantly different from those in the manganese chloride treatment group with 1.50% and 2.00%. In the relationship between the concentration of manganese chloride and the response of MDA in leaves, the change value of MDA in leaves of Conyza canadensis was low. MDA is an important index for plants in the stress environment, which can be used to evaluate the tolerance of Conyza canadensis to manganese and provide a theoretical basis for the ecological restoration of mining areas in the future.