Objective To investigate the effect of cyclic stretching on migration of MC3T3-E1 cells and related mechanism. Methods The strain loading system Flexcell-5000 was used to stretch MC3T3-E1 cells with 15% amplitude to simulate the mechanical condition in vivo. The wound healing assay was used to measure the migration of MC3T3-E1 cells. Western blotting was used to showed Runx2 expression. RNA interfering was used to decrease Runx2 expression. Results Cyclic stretching boosts migration of MC3T3-E1 cells. Decrease Runx2 expression can inhibit the migration of MC3T3-E1 cells and partially offset the effect of mechanical stretch on cell migration. Conclusion Cyclic stretch can promote the migration of MC3T3-E1 cells, and Runx2 may play an important role in this process. This study explored the mechanism of mechanical stretching promoting the migration of MC3T3-E1 cells, in order to provide experimental basis for finding innovative clinical treatment methods to promote fracture healing.