Targeting in vivo has been a spotlight for precise medicine. Multiple strategies including passive targeting and active targeting have been proposed for this issue. However, the efficiency remains to be improved. It has been thought that physical field-guided targeting is a beneficial supplement for the passive and the active targeting.Here, focused magnetic field was exploited to direct the targeting of magnetized erythrocytes in normal mice.The magnetic field-controlled targeting in vivo was found feasible. The systematic investigation about the aggregates in cerebral vessels showed that the aggregates were isotropic and able to stably exist for 6 hours. The formation of cellular aggregates can alter echoing characteristic of the blood vessels meaning the vascular wall became more rigid. If the erythrocytes were repeatingly directed into aggregation in an identical region, a stable plaque of erythrocytes can form, which can mimic the process of thrombosis.We believe these results will be beneficial to the novel engineered strategy for targeted delivery of drug carriers and the innovative modeling method of vascular diseases.