The　results　of　an　experimental　program　on　eight　short　reinforced　concrete　columns　having　different　structural　sizes　and　axial　compression　ratios　subjected　to　monotonic/cyclic　lateral　loading　were　reported.　A　3D　mesoscopic　simulation　method　for　the　analysis　of　mechanical　properties　of　reinforced　concrete　members　was　established,　and　then　it　was　utilized　as　an　important　supplement　and　extension　of　the　traditional　experimental　method.　Lots　of　numerical　trials,　based　on　the　restricted　experimental　results　and　the　proposed　3D　mesoscopic　simulation　method,　were　carried　out　to　sufficiently　evaluate　the　seismic　performances　of　short　reinforced　concrete　columns　with　different　structural　sizes　and　axial　compression　ratios.　The　test　results　indicate　that　(1)　the　failure　pattern　of　reinforced　concrete　columns　can　be　significantly　affected　by　the　shear-span　ratio;　(2)　increasing　the　axial　compression　ratio　could　improve　the　load　capacity　of　the　reinforced　concrete　column,　but　the　deformation　capacity　would　be　restricted　and　the　failure　mode　would　be　more　brittle,　consequently　the　energy　dissipation　capacity　could　be　deteriorated;　and　(3)　the　load　capacity,　the　displacement　ductility,　and　the　energy　dissipation　capacity　of　the　short　reinforced　concrete　columns　all　exhibit　clear　size　effect,　namely,　the　size　effect　could　significantly　affect　the　seismic　behavior　of　reinforced　concrete　columns.