Abstract: A description is considered of the masses of odd deformed atomic nuclei using fourth order polynomials for an odd nucleus’s deviations of N and Z. It is shown that moving from the second to the fourth order does not bring the parameters obtained for different groups of even–even nuclei closer to one another, and the higher order parameters calculated in this manner do not match satisfactorily. The smooth component of the mass of an odd nucleus is nearly the same for the fourth and second orders. It is concluded that it is entirely sufficient to consider second order polynomials.