Since completion of KVN construction in 2008 and commissioning in 2012, KVN has played an important role as an innovative mm-VLBI system, which has multi-frequency (22/43/86/129GHz) simultaneous observation capability for the first time in the world. Power of multi-frequency observation technique has been successfully demonstrated by KVN and now KVN style multi-frequency system is thought as a standard of future mm-VLBI system. In spite of KVN’s unique capability, KVN has a serious limitation as an array mainly due to the lack of baselines. In order to overcome this limitation and maximize science outcome using KVN, the extended KVN project (EKVN) is launched next year as a new mid-scale project with 8-year period. The immediate goals of the EKVN project are to construct a new KVN telescope and to upgrade receiving system. And it supports science activities with (E)KVN and international multi-frequency VLBI collaboration. I will introduces E-KVN project and its prospect in this talk.