The invention provides a sulfonated acetone-formaldehyde high-efficiency water reducing agent modified by enzymatic hydrolysis lignin or by derivatives thereof, and a preparation method thereof, raw materials comprise the enzymatic hydrolysis lignin or the derivatives thereof, acetone, aldehyde, sodium sulfite and sodium metabisulfite, a base catalyst and an acid regulator; the preparation steps comprise: mixing the sodium sulfite, the sodium metabisulfite with the water, heating at constant temperature and agitating, dropwise adding the acetone, adding the enzymatic hydrolysis lignin or the derivatives thereof, regulating pH value by the base catalyst, dropwise adding the aldehyde, continuous reacting for 3 hours, and adding the acid regulator to regulate the pH so as to result in product. The invention sufficiently utilizes reproducible biological resources, which not only solves the defect of low water reducing efficiency of the lignin-sulphonate water reducing agent extracted from papermaking 'black liquor' in the prior art, but also can replace partial petrochemical raw materials and reduce the production cost of the high-efficiency water reducing agent; the enzymatic hydrolysis lignin- or the derivatives thereof-modified high-efficiency water reducing agent has great use effect.