The anaerobic oxidation of isobutane over complex oxide catalysts of the type Cu
nV
2O
x (
n = 0, 1, 2, 3, and 5) was studied. V
2O
5, CuV
2O
6, and Cu
2V
2O
7 showed high oxidizing activity, and Cu
3V
2O
8 and Cu
5V
2O
10 were less active. Over the active catalysts, CO
2 was selectively formed only at the beginning of the reaction, and the rate of CO
2 formation decreased with reaction time. Isobutene formation became dominant 15–30 min after the start of the reaction. The rates of CO
2 and isobutene formation were lower over the less active catalysts, Cu
3V
2O
8 and Cu
5V
2O
10. The catalytic activity at 623 K decreased in the order V
2O
5 > CuV
2O
6, Cu
2V
2O
7 Cu
3V
2O
8, Cu
5V
2O
10. Because CO
2 formed at the beginning of the reaction, this system should be applicable for the selective formation of isobutene at appropriate reduction degrees. We concluded that CuV
2O
6 and Cu
2V
2O
7 should be applicable in a thin-layer reactor, in which isobutane and oxygen are separately supplied to opposite sides of the layer; in such a reactor, the catalyst surface on the isobutane side could be kept at a certain degree of reduction. Using the rate constants for isobutane consumption over Cu
2V
2O
7, we calculated the apparent activation energy for anaerobic oxidation of isobutane to be 87.6 kJ/mol, which agrees well with the reported value for a metal oxide catalyst. XPS analysis indicated that not V
5+ but Cu
2+ was reduced during the reduction of Cu
2V
2O
7 by H
2 at 473 K. Our results indicate that selective oxidation should be achievable over complex oxides that contain highly redox-active metal ions such as Cu
2+ if the reaction is carried out in a thin-layer reactor.