A method for producing a lubricating base oil, comprising: performing a 13C-NMR analysis regarding an oil to be treated and selecting the oil based on a value for dividing an integrated value of a peak for a tertiary carbon atom by an integrated value of all peaks at 0 to 50 ppm, a value for dividing an integrated value of a peak for a carbon atom constituting a main chain by the integrated value of all peaks at 0 to 50 ppm, and a value for dividing an integrated value of a peak for a branched CH3 bonded to a fifth or the following carbon atom from a terminal carbon atom in the main chain by an integrated value of all peaks at 10 to 25 ppm, and obtaining a dewaxed oil by isomerization dewaxing of the oil selected in the first step, is disclosed.