The invention discloses MBR and A2 / O based treatment method of waste lithium battery electrolyte and electrolyte waste water. Three treatment units are adopted for treatment. The treatment method comprises the steps of firstly treating waste electrolyte, then carrying out absorption by introducing a waste gas generated in the reaction of the electrolyte into waste water, so to remove the waste gas in a waste water treatment process, adopting Fenton oxidation to treat lithium battery waste water, so as to increase the biodegradability of the waste water, removing reaction sediment by sediment flocculation, using an A2 / O and MBR membrane separation and combination process to treat waste electrolyte , finally enabling effluent to pass through an RO (reverse osmosis) unit to ensure the effluent quality, and as for the concentrated water generated by RO, adopting a powdered activated carbon adsorption-ultrafiltration combined technology to remove organic pollutants in the concentrated water, so as to enable the treated water to reach the requirement of high-quality reuse water of RO. The treatment method overcomes the imperfection of a technic of recycling and treating a waste lithium battery in the past, and realizes reduction, harmlessness, reclamation of waste electrolyte waste water treatment.