Objective To investigate the effects of silenced Racl on invasion and migration in LOVo cells.Methods The expression of Racl mRNA and protein in colorectal cancer cells(including LoVo SW480.SW620.SW1116,HT29)were detected by RT-PCR and Western blot,respectively.The changes of cytoskeleton were observed in LoVO cells after transfected with Racl-shRNA.then invasion and migration were recorded respectively in LoVo cells after transfected with Racl-N17 and Racl-L61.Results Racl mRNA and protein were overexpressed in all selected colorectal cancer cells.Deletion of Racl decreased the cross-linked actin network and pseudopodia,and inhibited the invasion and migration in LoVo cells.The migration experiment showed that the migrated cells were higher in Racl-shRNA[(75±5)cells].Racl-N17 [(93±5)cells]and Racl-L61[(267±7)cells]groups compared with control group[(214±8)cells,P＜0.01,＜O.01 and＜0.05,resprectively].The invasion experimental study revealed that the migrated cells were higher in Racl-shRNA[(35±5)cells],Racl-N17[(42±5)cells]and Racl-L61[(86±7)cells] groups compared with control group[(73±6)cells,P＜0.01,＜0.01 and＜0.05,resprectively].Condusion Deletoin of Racl can inhibit the invasion and migration in LDVo cells.