The invention belongs to the technical field of waste plastic pyrolytic oil treatment, and discloses a waste plastic pyrolytic oil hydrodechlorination method which comprises the following steps: introducing waste plastic pyrolytic oil, and carrying out first-stage hydrotreatment on the basis of a first
metal sulfide catalyst in combination with preset first hydrogenation temperature, pressure, air speed and
hydrogen-oil volume ratio, performing first-stage hydrotreating on the waste plastic
pyrolysis oil to remove easily polymerized dialkene and monoolefine to obtain first-stage hydrotreated waste plastic
pyrolysis oil, and performing second-stage hydrotreating on the first-stage hydrotreated waste plastic
pyrolysis oil on the basis of a second
metal sulfide catalyst in combination with preset second hydrogenation temperature, pressure, air speed and
hydrogen-oil volume ratio to obtain a second-stage hydrotreated waste plastic
pyrolysis oil; organic chlorides are removed, olefin is converted into
alkane through hydrogenation, and dechlorinated waste plastic pyrolytic oil is obtained. According to the method, dialkene, monoolefine and organic chlorides in the waste plastic pyrolytic oil are removed, and the quality of the waste plastic pyrolytic oil is improved.