Air pollutants derived from diesel engines have more and more dangerous effect on the nature and on the built environment as well. One of the most important emission-component of a diesel engine running on conventional diesel is particulate matter. For measuring particulate matter there are many different widely used measurement methods. Using biofuel in diesel engines also causes emission of particulate matter. The basic aim of our work was to investigate and to evaluate the conventional biodiesel's and the new type TBK-Biodiesel's effect on the particulate relevant emission of a compression ignition engine. Particulate relevant emission mean in this case the four different measurement methods like filter smoke number, opacity, particulate mass and particulate number. With a rising blending rate of the - in internal combustion engine useable - bio derived fuels (standardized biodiesel and non standardized TBK-biodiesel) to fossil diesel the particulate relevant emission of the engine changes significantly. The tendencies in particulate relevant emission with growing blending rate are different among the measurement methods. Because of this situation biofuels cannot be evaluated clearly compared to fossil diesel in point of view of particulate relevant emission. (C) 2018 Elsevier Ltd. All rights reserved.