Japan National Route 170

{{short description|National highway in Japan}}

{{Infobox road

|country =JPN

|type =National

|route =170

|maint =

|alternate_name = Osaka Outer Loop Line

|map = {{Maplink2|zoom=9|frame=yes|plain=yes|frame-align=center|frame-width=300|frame-height=300|frame-latitude=34.6242|frame-longitude=135.4999

|type=line|stroke-color=#cc0000|stroke-width=2

}}

|map_custom=yes

|image =大阪外環状線（国道170号) 羽曳野IC前交差点付近 2010.9.06 - panoramio.jpg

|length_km =74.0

|length_round =

|length_ref ={{cite web|title=一般国道の路線別、都道府県別道路現況|trans-title=Road statistics by General National Highway route and prefecture|url=http://www.mlit.go.jp/road/ir/ir-data/tokei-nen/2016/pdf/d_genkyou26.pdf|language=ja|publisher=Ministry of Land, Infrastructure, Transport and Tourism|access-date=19 February 2020}}

|established = 1 April 1963

|direction_a = North

|terminus_a = {{jct|country=JPN|Route|171}} in Takatsuki, Osaka

|junction =

|direction_b = South

|terminus_b = {{jct|country=JPN|Route|26}} in Izumisano, Osaka

|previous_type=Route

|previous_route=169

|next_type=Route

|next_route=171

|browse=

}}

National Route 170 is a national highway of Japan connecting Takatsuki, Osaka and Izumisano, Osaka in Japan, with a total length of 74 km (45.98 mi).