In this paper, studies of V-Cs-Cu and V-Cs-Cu-TI catalysts used in the partial oxidation of p-tert butyl toluene to p-tert butyl benzaldehyde are reported. The two series of catalysts are prepared by an impregnation method. The effects of temperature, space velocity, concentration, ratio of O-2/p-tent butyl toluene and the stability of catalysts are examined. The results indicate that both the catalysts show good catalytic activity in partial oxidation of p-tert butyl toluene to p-tert butyl benzaldehyde; but the series of V-Cs-Cu-Tl catalysts exhibit more excellent catalytic activity. Under the reaction conditions of space velocity at 10,000 h(-1) and temperature at 440 degreesC, the conversion of p-tert butyl toluene can reach 12 mol% and the selectivity of p-tert butyl benzaldehyde is 85 mol%. In addition, the good stability in the series of V-Cs-Cu-TI catalysts is another important character: the catalytic activity still remained significant after stability test for 365 h.