In this paper, we give the normal form of all planar polynomial vector fields of degree d ࣘ 3 having two nonconcentric circles C 1 and C 2 as invariant algebraic curves and the function H=C β 1 C α 2 , with α and β real values, as first integral. Moreover, we classify all global phase portraits on the Poincaré disc of a subclass of these vector fields.