This paper explores the performance of pilot-scale constructed wetland osmotic microbial fuel cell (CW-OMFC) in different gravel conditions. The performance was measured in terms of power generation, water flux, chemical oxygen demand (COD) removal, and coulombic efficiency. The CW-OMFC was divided into four sections based on the porosity of the materials. The surface area of materials at Side A, Side B, Side C, and Side D were 2.717 m(2).g(-1), 0.228 m(2).g(-1), 0.095 m(2).g(-1), and 0.072 m(2).g(-1), respectively. The CW-OMFC achieved maximum water flux, minimum reverse salt flux, high power density, and COD removal efficiency of 6.66 +/- 0.5 L.m(-2).h(-1), 3.33 +/- 1.2 g.m(-2).h(-1), 59.53 +/- 10 mW.m(-2) and 84.69%, respectively, by using high porous materials. The nutrients (nitrogen, phosphorus, and potassium) uptake by plants from wastewater were 12.17%, 12.01%, and 21.73%, respectively.