The characteristics of phosphorus removal from the wastewater containing high concentrations of PO43− and NH4+ bystruvite formation in a jet loop crystallizer was investigated. By adding air into the jet loop crystallizer, the initial pH ofthe wastewater (pH=7.2) was gradually increased to 8.0 due to the CO2 stripping. As a result, the amount of causticchemicals added to maintain a desired level of operational pH of 8.5 could be reduced. The molar ratio of Mg:P in thewastewater used was always below 1. Therefore, the magnesium concentration was the limiting factor for struviteformation. To find the effective magnesium source, MgCl2, MgSO4, MgO, MgO+MgCl2, and MgO+MgSO4 were usedas a magnesium source. Among these chemicals, MgO+MgSO4 was the most effective in saving the operational cost.Throughout the experiments, a high percentage (89%) of phosphorus removal was achieved when MgCl2 was used asan Mg source. The removal efficiencies of phosphorus in the jet loop crystallizer with aeration were higher than thosein the crystallizer without aeration.