A process for upgrading pyrolysis oil that includes heating pyrolysis oil in the absence of added catalyst at 100° C. to 200° C. temperature and 50 bar to 250 bar pressure, and heating the product of the first heating in the absence of added catalyst at 200° C. to 400° C. temperature and 50 bar to 250 bar pressure. Also, the product obtained by this process and the use of treated pyrolysis oil. Further, methods where the treated pyrolysis oil is fed to a power plant for producing electricity; is burned in a boiler for producing heating oil and/or is used as transportation fuel or as a blending component in transportation fuel.