Abstract: In mixture problems,additional mixture constraints often are imposed.For the set of low and super bound constraints of individual component,we show that only exist two types of the inconsistent constraints,either the components have single- sided,constraint or one component only has a both-sided inconsistent constraints.It can’t happen that two components have ineonsistent constraints on both sides.For the set of low and super bound constraints of multicomponents and the set of complex constraints,we give respective judgement methods on the superfluous constraints. These judgement methods are illustrated with several numerical examples.