Poultry manure anaerobic digestion effluent (PMADE) contained a high content of ammonia nitrogen (NH4+–N), which should be treated properly before discharge. However, the mechanism of electrolysis in treating high NH4+–N (over 1,500 mg L–1) wastewater has never been studied. In this study, fertilizer wastewater from PMADE with high content of NH4+–N (over 3,000 mg L–1) and low carbon/nitrogen (C/N) ratio was treated via electrolysis and microalgae. Results showed the highest removal of NH4+–N, total organic carbon (TOC) and inorganic carbon (IC) in electrolysis were 47%, 76%, and 93%, respectively. Quadratic functions are suitable to simulate NH4+–N removal of FW (coefficient is over 0.95). The removal efficiency of NH4+–N was 10%–65% during microalgae cultivation. The removal of NH4+–N, total phosphorus (TP), IC, and TOC in fertilizer wastewater by the combination of electrolysis and microalgae cultivation achieved 96%, 63%, 95%, and 52%, respectively. Chlorella sp. used 3.11% carbon, 15.0% nitrogen, and 13.5% phosphorus in the FW as substrates. This study provided an alternative approach to treat and reuse high-ammonia containing wastewater.