The invention discloses a method of treating high-concentration metaformaldehyde waste water into reuse water, relating to a treatment technology of high-concentration metaformaldehyde waste water. The pH of metaformaldehyde waste water of which the formaldehyde content is 4000mg/L into 3.0-4.0, then metaformaldehyde waste water is sent into an anaerobic hydrolysis composite reactor combining activated sludge with biomembrane and an aerobic composite reactor; at last, a double-membrane method is adopted to treat to ensure that effluent reaches the standard of urban wastewater recycling industrial water quality, thus serving as recirculated cooling water. The invention strengthens removal of high-concentration formaldehyde, COD, trioxymethylene, divinylene oxide and other pollutants in high-concentration metaformaldehyde waste water by biological treatment, can effectively resist impact from violent water yield and water quality, and has the advantages of high system starting speed, small foam of the aerobic composite reactor, low operation cost, stable and effective treatment and zero discharge of waste water.