An　experimental　investigation　was　conducted　to　evaluate　the　axial　compressive　behaviour　of　circular　hollow　section　(CHS)　stub　columns　with　initial　crack　defects.　A　total　of　96　specimens　?　12　stub　columns　with　one　crack,　48　stub　columns　with　two　cracks,　and　36　stub　columns　with　three　cracks　?　were　tested　under　axial　compression　loading.　The　failure　modes,　load-carrying　capacities,　overall　deflections,　and　strain　intensities　of　all　the　specimens　were　examined.　The　design　parameters　were　the　tube　thickness,　long　crack　length,　short　crack　length,　crack　spacing,　and　crack　number.　Additionally,　a　finite-element　analysis　was　performed　using　the　verified　models　in　combination　with　the　experimental　data　to　evaluate　the　effects　of　the　main　influential　factors.　The　initial　cracks　formed　in　the　circular　thin-walled　stub　columns　accelerated　the　local　buckling　and　changed　both　the　bearing　capacity　and　deformation　capacity.　The　ultimate　loads　of　the　stub　columns　increased　with　the　tube　thickness,　decreased　slightly　with　an　increase　in　the　long　crack　length,　and　decreased　with　an　increase　in　the　crack　spacing.　The　effects　of　the　short　crack　length　and　crack　number　on　the　bearing　capacity　were　complex　and　were　coupled　with　the　tube　thickness.　An　adjustment　coefficient　was　introduced　into　the　predictive　formula　to　estimate　the　ultimate　bearing　capacity.　Through　this,　the　ultimate　bearing　capacity　can　be　accurately　predicted.