The estimation of sloshing loading on liquid tanks is of fundamental importance due to the wide and important applications of liquid tanks in various engineering aspects. Analytical solutions for the sloshing loading on circular cylindrical liquid tanks with an interior concentric vertical thin semi porous barrier under external excitations are presented. And the extensions of the solutions to the elastic vibrations and to the high frequency limit to count for the earthquake response are also included. A clear view on the influence of semi porous barriers to the sloshing response of oscillating tanks is obtained by the analyses of systematic computational results. The present results may offer guidance to the corresponding design for liquid tanks of various applications and also a basis of comparison for the development of more sophisticated numerical methods for hydrodynamic and hydro elastic analyses. The estimation of sloshing loading on liquid tanks is of fundamental importance due to the wide and important applications of liquid tanks in various engineering aspects. Analytical solutions for the sloshing loading on circular cylindrical liquid tanks with an interior concentric vertical thin semi porous barrier under external excitations And presented extensions to the solutions to the elastic vibrations and to the high frequency limit to count for the earthquake response are also included. A clear view on the influence of semi porous barriers to the sloshing response of oscillating tanks is obtained by the analyses of systematic computational results. The present results may may offer guidance to the corresponding design for liquid tanks of various applications and also a basis of comparison for the development of more sophisticated numerical methods for hydrodynamic and hydrolastic analyzes.