Further experimental evidences of redispersion on supported platinum catalysts studied by means of TPR, TPD and cyclohexene hydrogenation reaction. Pt/r-Al₂O₃ exhibits stronger interaction between the metal oxide and the support as compared with Pt/SiO₂ and Pt/TiO₂. The formation of surface complex is enhanced as oxidation temperature increases. The TPD spectrum of hydrogen on Pt/TiO₂ shifts to higher temperature upon reduction at high temperature and shifts again to its original position upon oxidation. Shift of TPD spectrum does not appear in other catalysts. The suggested mechanism for redispersion is the spreading of platinum oxide and trapping of migrating species.