One of the advantages of organic light-emitting diode(OLED) over other display technologies is the ability to fabricate on flexible substrates.As polymer substrate dose not offer the same barrier performance as glass,OLED on polymer substrate will require thin-film barriers on both of the bottom and top side of the device layers to make better packages for sufficient lifetime.The recent development of encapsulation for OLED was described,and some encapsulation methods were provided.