A filter for filtering pyrolysis oil and an arrangement. The filter is a split-flow filter (1, 1a, 1b), comprising a filter element (12), comprising plurality of apertures (17) extending through the filter element (12), a receiving channel (13) for receiving a flow (F) of pyrolysis oil to be filtered and for supplying said flow on first side (A) of the filter element (12), a main discharge channel (14) arranged on the first side (A) of the filter element (12) for discharging the portion of the flow (F) of pyrolysis oil having not penetrated through the filter element (12), and a filtrate channel (15) arranged on second side (B) of the filter element (12) for discharging the portion of the flow (F) of pyrolysis oil having penetrated through the filter element (12).