During the last decades, constructed wetlands (CW) were very successful when used forrntreatment of wastewater from different sources such as municipal, domestic, industrial,rnagricultural and surface runoff. This new approach is designed based on natural processesrninvolving complex and concerted interactions between the plants, the substrate and therninherent microbial community to accomplish wastewater treatment in a more controlled andrnpredictable manner through physical, chemical and biological processes.rnIn order to evaluate the performance of constructed wetland and generate information a totalrnof 24 samples were collected and analyzed for selected wastewater quality parameters fromrna Jehovah Witnesses Branch Office wetland constructed to treat domestic wastewater. Thernparameters analyzed were biochemical oxygen demand, chemical oxygen demand, totalrnsuspended solids, ammonium N, nitrate N, total N, orthophosphate, total phosphorus,rnsulfate, sulfide, temperature, pH, total coliform and fecal coliform. They were all measuredrnusing standard methods.rnThe treatment performance of JWBO wetland was evaluated based on the percentagernremoval efficiency of the above parameters. Within the study period, the mean removalrnefficiency of JWBO CW system was 99.3% (BOD5), 89% (COD), 85% (TSS), 28.1%rn(NH4rn+-N), 64% (NO3-N), 61.5% (TN), 28% (orthophosphate), 22.7% (TP), 77.3% (Sulfate),rn99% (Sulfide), 94.5% (TC) and 93.1% (FC).rnMoreover, though the difference is not as such high, the result of this study indicated thatrnwetland cells planted with Cyprus papyrus (cell 1 and 3) showed higher removal efficiencyrnfor NO3-N (82.4%), NH4rn+-N (24.8%), TN (54.8%), PO4rn3- (23.5%), and TSS (83.9%) thanrnthe other wetland cells. Similarly wetland cells planted with Phoenix canariensis (cell 4 andrn6) showed higher removal efficiency for TP (17%), S2- (99%), BOD5 (98%), COD (90%),rnTC (94%) and FC (91%). While the other wetland cells planted with Cyprus alternifoliarn(cell 2 and 5) showed higher removal efficiency only for SO4rn2- (82.2%) than the others.rnHowever, these differences were statistically significant (p