In　this　paper,　413　experimental　results　from　circular　concrete-filled　steel　tube　short　columns,　which　were　subjected　to　formulae　under　the　design　specifications　of　CECS　28:　2012(19),　AIJ　(2008)(20),　ANSI　/AISC　360-05(21)　and　EC4　(2004)22　are　presented.　Generally,　when　the　specimen　diameter　increases,　the　ratio　of　experimental　values　to　calculated　values　decreases;　this　illustrates　the　influence　of　existent　size　effect　on　the　compression　strength　of　concrete-filled　steel　tube　columns.　The　correction　coefficients　of　size　effect　obtained　from　the　data　fitting　were　subjected　to　the　formulae.　Subsequently,　the　experimental　values　to　calculated　values　ratio　did　not　change　with　size　of　the　specimen.　Having　considered　1.0　as　the　critical　value　of　the　confinement　index,　the　data　were　divided　into　two　groups.　When　the　correction　coefficients　of　the　two　groups　using　the　same　formula　were　compared,　it　was　seen　that　the　smaller　the　confinement　index　was,　the　larger　the　size　effect　would　be.　When　the　results　obtained　from　different　formulae　were　compared,　the　size　effect　on　the　formulae　using　the　confinement　index　was　found　to　be　smaller　than　that　on　the　formulae　with　a　superposition　form　of　capacity.