The rate constants of bulk electron-ion recombination in dense gaseous argon and krypton have been calculated by means of computer simulation. The electron scattering in those systems was modeled by the low-pressure energy-dependent cross sections for elastic collisions with gas atoms. The applicability of the assumed cross sections to the considered systems was verified by the calculation of the electron mobility in an external electric field. The recombination rate constants determined from our simulation are two orders of magnitude lower than the experimental results. Possible reasons for this disagreement are discussed.