Using the comparion theorem of difference equation, persistence theorem of discrete semi-dynamical system and stability of monotonous operator, we gain the boundary, uniform persistence and permanence of the system.
Using the theorem on discrete semi-dynamicl system and the stability results on monotonous and continuous operator,we obtained the sufficent conditions for uniform boundness,strong and weak persistence and permanence of a discrete system with age-structure subdivided into young and adult population approximately.