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【Objective】 Constructed wetland is a biotechnological technique to treat wastewater; its function depends on a multitude of biotic and abiotic factors. This paper compares the performance of eight wetlands constructed by different materials. 【Method】 The eight wetlands we studied were constructed by fine sand only (CK), fine sand + corn straw powder (JW), fine sand + industry glucose (PW), sand + corn-straw biochar (SW), fine sand + eisenia fetida (KQ), fine sand + corn straw powder + eisenia fetida (JQ), fine sand + industrial glucose + eisenia fetida (PQ), fine sand + corn stover biochar + eisenia fetida (SQ), respectively. 【Result】 Adding corn-straw biochar, industrial glucose and corn-straw power increased the COD removal rate by 81.80%, 88.58% and 85.77%, respectively, compared to CK. Adding industrial glucose combined with corn straw powder improved purification efficiency of total N (TN) and total P (TP) by 7.0% and 2.8%, respectively. Wetland with industrial glucose and corn straw powder had the best TN removal rate, reaching 98% and 98.2%, respectively. Adding corn-straw power along with eisenia fetida was most effective to remove cooper, compared with other treatments. On average, introducing eisenia fetida to the wetlands increased the removal rates of COD, Cu and Zn by 1.8%, 6.3% and 2.6%, respectively, while adding corn-stover biochar significantly increased the removal rate of NH4+-N. Compared with corn straw powder and corn straw biochar, industrial glucose was more efficient for removing COD, total N and N, and Cu. 【Conclusion】 Adding eisenia fetida and organic carbon to the wetland can improve its efficacy to remove COD, nitrogen and heavy metals, especially corn-stover powder combined with eisenia fetida. For removing Cu, corn straw powder combined with eisenia fetida works the best.