Abstract: The concept lattice is useful in knowledge processing and analying.And it has been used with a high intensity to knowledge reduction and data mining.This paper first puts forward information quantity of concept lattice extension，then studies new and relatively reasonable formulas measuring attribute significance and proposes a theory for justifying whether an attribute is a key attribute on concept lattice or not.And then those formulas are used as heuristic information to design a novel and heuristic algorithm for attribute reduction on concept lattice.Finally，a real example is used to demonstrate both its feasibility and effectiveness.