Upgrading a fraction of a heavy Fischer-Tropsch oil to jet fuel by hydropretreating a 350.degree. to 850.degree. F boiling fraction; separating the hydrotreated product into a 650.degree. F minus and a 650.degree. F plus fraction, separating the650.degree. F minus fraction to provide a 350.degree. F minus naphtha boiling range fraction and a 350.degree. to 650.degree. F light distillate fraction; distilling the 350.degree. to 650.degree. F hydrotreated fraction to provide a fraction boiling in the range of 350.degree. F to 550.degree. F separate from a 550.degree. to 650.degree. F fraction processing either of the 650.degree. F plus fraction above separated or the 350.degree. to 550.degree. F boiling fraction above obtained over a catalyst comprising a crystalline aluminosilicate zeolite having a silica to alumina ratio of at least 12 and a constraint index of 1 to 12 with hydrogen, at a temperature of about 500.degree. to 800.degree. F, a hydrogen partial pressure of about 100 to 800 psig and a space velocity in the range of about 0.5 to 5 LHSV to produce a converted product comprising lower boiling hydrocarbons than the feed charged and recovering as a product of the process a reduced pour point diesel oil fraction, a 350.degree. to 550.degree. F jet fuel fraction, and a 350.degree. F minus naphtha product fraction.