A method for producing a hydrocarbon-based lubricating base oil comprising: a step of hydrocracking/hydroisomerization of a feed stock oil containing normal paraffins, so that: a urea adduct value of an obtained treated product is not greater than 4 % by mass, a viscosity index is 130 or higher, an average of carbon atoms number is 27-31, a value obtained by dividing an integral value of a peak in 30 ppm by an integral value of total peaks in the range from 0 ppm to 50 ppm for the 13 C-NMR spectrum is 0.1-0.2, and a product of a value obtained by dividing an integral value of peaks attributed to tertiary carbon atoms by an integral value of total peaks in the range of from 0 ppm to 50 ppm for the 13 C-NMR spectrum and the average of carbon atoms number is 1.8-2.5; or a urea adduct value of an obtained treated product is not greater than 4 % by mass, a viscosity index is 100 or higher, an average of carbon atoms number is greater than 23 and less than 27, a value obtained by dividing an integral value of a peak in 30 ppm by an integral value of total peaks in the range from 0 ppm to 50 ppm for the 13 C-NMR spectrum is 0.1-0.2, and a product of a value obtained by dividing an integral value of peaks attributed to tertiary carbon atoms by an integral value of total peaks in the range of from 0 ppm to 50 ppm for the 13 C-NMR spectrum and the average of carbon atoms number is 1.8-2.5, wherein the step of hydrocracking/hydroisomerization comprises: a first step in which a normal paraffin-containing stock oil is subjected to hydrotreatment using a hydrotreatment catalyst, a second step in which the treatment product from the first step is subjected to the hydrodewaxing using a hydrodewaxing catalyst, and a third step in which the treatment product from the second step is subjected to hydrorefining using a hydrorefining catalyst, wherein the "urea adduct value" and the "average of carbon atoms number" are measured as described in the description. a step of hydrocracking/hydroisomerization of a feed stock oil containing normal paraffins, so that: a urea adduct value of an obtained treated product is not greater than 4 % by mass, a viscosity index is 130 or higher, an average of carbon atoms number is 27-31, a value obtained by dividing an integral value of a peak in 30 ppm by an integral value of total peaks in the range from 0 ppm to 50 ppm for the 13 C-NMR spectrum is 0.1-0.2, and a product of a value obtained by dividing an integral value of peaks attributed to tertiary carbon atoms by an integral value of total peaks in the range of from 0 ppm to 50 ppm for the 13 C-NMR spectrum and the average of carbon atoms number is 1.8-2.5; or a urea adduct value of an obtained treated product is not greater than 4 % by mass, a viscosity index is 100 or higher, an average of carbon atoms number is greater than 23 and less than 27, a value obtained by dividing an integral value of a peak in 30 ppm by an integral value of total peaks in the range from 0 ppm to 50 ppm for the 13 C-NMR spectrum is 0.1-0.2, and a product of a value obtained by dividing an integral value of peaks attributed to tertiary carbon atoms by an integral value of total peaks in the range of from 0 ppm to 50 ppm for the 13 C-NMR spectrum and the average of carbon atoms number is 1.8-2.5, a urea adduct value of an obtained treated product is not greater than 4 % by mass, a viscosity index is 130 or higher, an average of carbon atoms number is 27-31, a value obtained by dividing an integral value of a peak in 30 ppm by an integral value of total peaks in the range from 0 ppm to 50 ppm for the 13 C-NMR spectrum is 0.1-0.2, and a product of a value obtained by dividing an integral value of peaks attributed to tertiary carbon atoms by an integral value of total peaks in the range of from 0 ppm to 50 ppm for the 13 C-NMR spectrum and the average of carbon atoms number is 1.8-2.5; or a urea adduct value of an obtained treated product is not greater than 4 % by mass, a viscosity index is 100 or higher, an average of carbon atoms number is greater than 23 and less than 27, a value obtained by dividing an integral value of a peak in 30 ppm by an integral value of total peaks in the range from 0 ppm to 50 ppm for the 13 C-NMR spectrum is 0.1-0.2, and a product of a value obtained by dividing an integral value of peaks attributed to tertiary carbon atoms by an integral value of total peaks in the range of from 0 ppm to 50 ppm for the 13 C-NMR spectrum and the average of carbon atoms number is 1.8-2.5, wherein the step of hydrocracking/hydroisomerization comprises: a first step in which a normal paraffin-containing stock oil is subjected to hydrotreatment using a hydrotreatment catalyst, a second step in which the treatment product from the first step is subjected to the hydrodewaxing using a hydrodewaxing catalyst, and a third step in which the treatment product from the second step is subjected to hydrorefining using a hydrorefining catalyst, wherein the "urea adduct value" and the "average of carbon atoms number" are measured as described in the description. a first step in which a normal paraffin-containing stock oil is subjected to hydrotreatment using a hydrotreatment catalyst, a second step in which the treatment product from the first step is subjected to the hydrodewaxing using a hydrodewaxing catalyst, and a third step in which the treatment product from the second step is subjected to hydrorefining using a hydrorefining catalyst, wherein the "urea adduct value" and the "average of carbon atoms number" are measured as described in the description.