A method is taught for producing diesel fuels of high cetane value from a triglyceride feedstock, comprising pretreating the triglyceride feedstock by thermal cracking to partially convert the triglycerides and produce a middle distillates stream, and catalytically hydrotreating the middle distillate fraction to produce high cetane value diesel fuels. A biomass-derived diesel fuel is also taught having sulphur content below 10 ppm, a cetane-value of at least 70, a cloud point below 0° C. and a pour point of less than −4° C. A blended diesel fuel is also taught comprising 5 to 20 vol. % of the biomass-derived diesel fuel of the present invention and 80 to 95 vol. % of a petroleum diesel, based on total volume of the blended diesel fuel.