The catalytic behaviour of vanadyl pyrophosphate in the conversion of either n-butane, 1-butene, n-pentane or 1-pentene is reported. The results obtained indicate that the product selectivity and hydrocarbon conversion can be changed by varying the temperature and GHSV. The choice of doping elements has a significant effect on hydrocarbon conversion and product yield, much more than surface area. The maleic anhydride yield increases strongly with an increase in catalyst acidity when n-butane and n-pentane are feed materials. With the corresponding olefins the effect due to acidity is insignificant.