This paper reports effect of inorganic ions on removal of organic pollutants over the g-C3N4 polymer photocatalyst by photocatalysis. The oxidation of SO32- by photogenerated hole on g-C3N4 will induce a chain reaction initialed by SO32- to form (OH)-O-center dot while the hole oxidation of SO32- increases the separation of photogenerated electron and hole, which process promotes the photogenerated electron induced multistep reduction of O-2 generating (OH)-O-center dot to proceed. On the other hand, the cation, Na+, can interact with the negatively charged nitrogen pots in the C3N4 sheets via the ion dipole interaction. Such ion dipole interaction significantly improves the charge separation and transport, thus accelerating the formation of active species ((OH)-O-center dot). As a result of positive effect of Na+ and SO32- on photocatalysis of g-C3N4, the degradation rates of organic pollutants over g-C3N4 were significantly increased. Our studies offer the new opportunities for using the g-C3N4 with low cost and facile adjustable function to treat industrial wastewater containing organic pollutants. (C) 2014 Elsevier B.V. All rights reserved.