Abstract: Objective: To investigate the effects of circBIRC6 on the malignant biological behavior of colorectal cancer cells and its targeted regulation on miR-944. Methods: The expression levels of circBIRC6 and miR-944 in colorectal cancer tissues and adjacent tissues were detected using qRT-PCR.In vitro,human colorectal cancer cells SW480 were cultured,and divided into the si-NC group(transfected with si-NC),si-cicBIRC6 group(transfected with si-cicBIRC6),miR-NC group(transfected with miR-NC),miR-944 group(transfected with miR-944 mimics),si-cicBIRC6+anti-miR-NC group(transfected with si-cicBIRC6 and anti-miR-NC),and si-cicBIRC6+anti-miR-944 group(transfected with si-cicBIRC6 and anti-miR-944).The MTT,plate clone formation test,scratch test and Transwell chamber test were used to detect cell proliferation,clone formation,migration and invasion,respectively.The dual luciferase reporter gene experiment was used to detect the targeting relationship between circBIRC6 and miR-944.The Western blotting was used to detect the expression levels of E-cadherin and N-cadherin protein. Results: The expression level of circBIRC6 in colorectal cancer tissue was higher than that in adjacent tissues,and the expression level of miR-944 was lower than that in adjacent tissues(P<0.01).Compared with the si-NC group,the cell viability,scratch healing rate,clone formation number,invasive cell number,and N-cadherin protein level in the si-circBIRC6 group decreased(P<0.01),while the E-cadherin protein level increased(P<0.01).Compared with the miR-NC group,the cell viability,scratch healing rate,number of clone formation,number of invasive cells,and N-cadherin protein levels in the miR-944 group decreased(P<0.01),while the E-cadherin protein level increased(P<0.01). Conclusions: Interfering circBIRC6 can inhibit the proliferation,colony formation,migration and invasion of colorectal cancer cells by targeting miR-944.