Propane was dehydrogenated to propene at 873 K optionally under He and CO2 (1 atm) over Cr, V, Ga and Fe oxides supported on MCM-41 mesoporous silica. The CO2/propane and He/propane ratios were 5. The MCM-41 support (pore size and vol. 2.4 nm and 0.9 cm(3)/g, resp., sp. surface 1085 m(2)/g) was prepd. by hydrolysis of (EtO)(4)Si in presence of Me-3(C-16 H-33) NCl and NH3 in aq. medium (pH 89). The catalysts were prepd. by impregnation with resp. salts to the metal content 0.53 mmole/g after calcination. The catalytic activity of the catalysts decreased in the series Cr > V > Ga > Fe. The addn. of CO2 resulted in an increase in the reaction selectivity to propene. The highest propane conversion (48%.), propene yield (46.2%) and propene selectivity (88.7%) were achieved When Cr oxide catalyst was used.