The temperature (T) dependence of the resistivity due to the electron-electron scattering in two-dimensional Fermi systems is discussed. First, we consider an isotropic Fermi system. It is shown that the resistivity is proportional to T2, if 4k(F) is larger than the smallest absolute value of the reciprocal lattice vectors, though the T-dependence of the damping is T2 ln T. Next, we consider the Hubbard model. In the half-filled case, the resistivity is proportional to T ln T. The logarithmic correction is due to van Hove singularity. In the nearly half-filled case, it is pointed out that the main T-dependence of the resistivity is not T, but T2, and that the discussion on the T-dependence of the resistivity in the nested Fermi-liquid presented recently by Virosztek and Ruvalds is misleading.
