The invention relates to a process for converting paraffin to olefin comprising the following steps: (a) providing a hydrocarbon feedstock containing at least one paraffin having 1 to 12 carbon atoms and at least one olefin having 2 to 12 carbon atoms; (b) providing a catalyst containing at least one Group VIA and/or Group VIIA transition metal on a solid support; (c) pretreating the catalyst by contacting the catalyst with at least one reducing gas and at least one oxidizing gas; and (d) contacting the by hydrocarbon feedstock and the pretreated catalyst at a temperature in the range of 200° C. to 600° C., preferably 320° C. to 450° C. and to a catalyst for use therein.