Chiascio

{{Infobox river

| name = Chiascio

| image =

| image_caption = Chiascio

| map = Chiascio.png

| source1_location = Monte Cucco

| source1_elevation = {{convert|850|m|abbr=on}}

| mouth = Tiber

| mouth_location = Torgiano

| mouth_coordinates = {{coord|43|01|06|N|12|25|50|E|region:IT-PG_type:waterbody_source:kolossus-dewiki|display=it}}

| progression = {{RTiber}}

| subdivision_type1 = Country

| subdivision_name1 = Umbria, Italy

| length = {{convert|95|km|abbr=on}}

| discharge1_avg = {{convert|20|m3/s|abbr=on}}

| basin_size = {{convert|1962|km2|abbr=on}}

}}

The Chiascio is a river of Umbria, central Italy. It is a left tributary of the Tiber. It is 95 km long, and its drainage basin covers 1962 km². Its largest tributary is the Topino, which covers 60% of its drainage basin.Agenzia regionale di protezione ambientale dell'Umbria, [http://www.arpa.umbria.it/AU/documenti/acqua/Unit%C3%A0%20territoriali.pdf Caratterizzazione dei bacini idrografici e dei corpi idrici superficiali], Sottobacino Chiascio , p. 7 of 22.