A　new　universal　monochrome　display　system　for　OLED　or　LCD　is　presented.　Based　upon　this　system,　designers　can　develop　their　own　application　software　conveniently,　by　using　its　abundant　functions.　This　system　coded　in　C　adopts　OOAD　(Object-Oriented　Analysis　and　Design)　such　as　encapsulation　and　inheritance.　This　possesses　some　benefits　for　software　development.　The　system　consists　of　two　layers　in　embedded　system　and　a　font　building　tool　in　PC　platform.　Al　last,　the　parting　and　testing　is　presented　respectively.