The influence of two oxygenated tailor-made fuels on the soot formation and oxidation in an optical single cylinder research diesel engine has been studied. For the investigation a laser-induced incandescence (LII) measurement technique was applied to the engine in order to detect and evaluate the planar soot distribution for the different bio fuels within a laser light sheet. Furthermore the OH* chemiluminescence and broad band soot luminosity was visualized by high speed imaging to compare the ignition and combustion behavior of tested fuels: Two C8 oxygenates, di-n-butylether (DNBE) and 1-octanol were investigated. Both fuels have the same molecular formula but differ in their molecular structure. DNBE ignites fast and burns mostly diffusive while 1-octanol has a low cetane number and therefore it has a longer ignition delay but a more homogeneous mixture at time of ignition as shown in a previous study. The two bio fuels were finally compared to conventional diesel fuel. The heat release reactions after ignition by means of the OH* chemiluminescence shows the fast igniting behavior of DNBE with soot formation being slightly delayed. The soot formation for DNBE is very similar to that of conventional diesel fuel. However the amount of soot formed is lower and starts oxidizing earlier in the cycle according to the LII signal. The OH* chemiluminescence signal of 1-octanol on the other hand shows a rapid burn out in the combustion chamber. Due to the homogenous mixture hardly any soot formation takes place.