In　the　sewage　treatment　process,　the　dissolved　oxygen　concentration　is　a　very　important　control　target,　but　it　is　difficult　to　be　controlled.　To　solve　this　problem,　a　self-organizing　fuzzy　neural　network　controller　based　on　genetic　ideas　(G-SOFNN)　is　proposed.　In　the　controller　structure　reduction　process,　the　deleted　neuron　information　is　merged　with　the　remaining　neurons　to　reduce　the　interference　set.　During　the　controller　structure　increasing　phase,　the　information　of　new　neurons　is　initialized　to　avoid　overlapping　of　information.　Then,　the　controller　parameters　are　trained　by　the　projection　algorithm　to　improve　the　control　precision.　Experiments　illustrate　that　the　proposed　method　can　accurately　control　the　concentration　of　dissolved　oxygen　in　the　sewage　treatment　process.　©　2019,　ICST　Institute　for　Computer　Sciences,　Social　Informatics　and　Telecommunications　Engineering.