Rates of solid-liquid mass transfer at an oscillating packed bed of Raschig rings contained in a wire mesh cage were studied using the diffusion-controlled dissolution of copper in an acidified dichromate technique. Variables studied were the frequency and amplitude of bed oscillation, mesh number of the screen forming the bed container, ring diameter, bed diameter, bed height, bed separation in the case of a multibed reactor, and effect of superimposed axial flow. Container mesh number and bed diameter were found to have little effect on the rate of mass transfer. The data with no net solution flow (batch reactor) were correlated by the equation Sh = 0.76Sc(0.33)Re(v)(0.7)(d(c)/h)(0.35). Superimposed axial laminar flow was found to increase the rate of mass transfer while turbulent flow Was found to decrease the rate of mass transfer at the oscillating bed. Practical implications of the present work for designing a high space time yield reactor suitable for conducting liquid-solid heterogeneous and catalytic reactions are noticed.