Thin　film　electrodes　on　a　flexible　substrate　have　attracted　significant　interests　from　the　community　for　developing　flexible　and　wearable　electronics.　A　prompted　routine　for　inkjet　printing　conductive　patterns　on　a　flexible　plastic　substrate　is　developed　in　this　study,　in　which　silver　ion-based　catalytic　ink　is　utilized　as　a　seed　layer　for　electroless　copper　metallization　in　room　temperature.　Through　optimization　of　Ag+　ink　composition　and　printing　process　parameters,　the　pattern　definition　and　continuity　of　electroless　plated　Cu　have　been　improved.　The　resistivity　at　the　same　order　of　10(-6)　Omega　cm　as　bulk　copper　is　achieved,　and　the　adhesion　has　passed　a　variety　of　mechanical　tests.　Comprehensive　characterizations　of　the　printed　samples　at　various　processing　stages　are　carried　out　and　presented　in　this　paper.