Objective To explore the interaction of Anxa2 with P-Glycoprotein(P-gp) in the migration and invasion of the multidrug-resistant (MDR) human breast cancer cell line MCF-7/ADR. Methods A pair of short hairpin RNA(shRNA) targeting P-gp was transfected into MCF-7/ADR cells,and monoclonal cell strains were screened.The expression of P-gp was detected by Western blot.Transwell chambers were used to observe the cell migration capacity and invasion ability.The interaction between P-gp and Anxa2 was examined by immunoprecipitation and immunofluorescence confocal microscopy analyses. Results P-gp expression was significantly knocked down,and there were notable decreasing trends in the migration and invasion capability of MDR breast cancer cells(P<0.05).There was a close interaction between Anxa2 and P-gp. Conclusions MCF-7/ADR is an MDR human breast cancer cell line with high migration and invasion abilities.The knockdown of P-gp notably impaired the migration and invasion abilities of the tumor cells.The interaction of Anxa2 with P-pg may play an important role in the enhanced invasiveness of MDR human breast cancer cells.