For joint retrieval of vertical distributions of both air density and ozone concentration in the mesosphere which are two of the most important atmospheric parameters in this region, a retrieval scheme is suggested by using satellite limb scan observation at two UV wavelengths, i.e. 255 nm and 296 nm. The retrieval scheme is the modification of the direct method by Aruga and Heath with two UV wavelengths and two atmospheric parameters. Feasibility study was made based on simulated limb scan radiances computed with a single scattering radiative transfer algorithms of spherical geometry developed by the present authors and the inversion technique. Results of the simulations show that it is feasible to retrieve air density and ozone concentration vertical distributions on a global basis from satellite UV limb scan over the altitude range of 50 km～ 100 km with a vertical resolution of 1 km. The errors of the inferred profiles by using the joint inversion algorithm are greatly deduced, especially in the upper-mesosphere heights, compared with those by using the single inversion technique with a single wavelength.