We found that microglia and a small part of bone marrow derived progenitor cells had a specific affinity and migrating activity to the brain. The migration seemed to occur without breakage of blood brain barrier. To demonstrate the specific migration by in vivo micro imaging, we assembled a high-speed laser confocal microscope and applied it to investigate the flowing cells injected in blood stream as a funduscopy. For in vivo macro imaging we successfully observed the cell migration by MRI with an iron oxide particle cell labeling technique. We also tried to investigate such cell migration by in vivo fluorescent imaging system and detected the cells labeled with Qdot800.