The paper mill effluent might be used for degraded wetlands restoration due to its abundant organic substances. Chemical properties including soil pH, total soluble salts, Na+, Cl- and soil nutrients of a heavily degraded coastal saline-alkaline wetland were studied after irrigation with treated paper mill effluent. The result showed that the soil pH increased a little without leading to aggravation of the soil alkalization. Compared to the control, the total soluble salts, Na+ and Cl- decreased by 9.61%-37.05%, 3.16%-21.66% and 5.38%-28.44% respectively, and the reduction rates of upper soil layers were higher than those of the middle and lower layers. Irrigation of paper mill effluent significantly improved the soil organic matter, alkali-hydrolyzable N and available P with the increasing rates higher than the control by 13.68%-3145%, 30.01%-101.07% and 1.08%-18.28% respectively. While available K did not rise significantly. A comparison with natural reed wetlands showed that irrigation with treated paper mill effluent could improve the soil property of the heavily degraded coastal wetland to the level suitable for reeds restoration and reed wetlands reconstruction.