Lunain

{{Infobox river

| name = Lunain

| image =

| image_caption =

| map = Lunain.png

| source1_location = near Égriselles-le-Bocage

| source1_coordinates= {{coord|48|06|38|N|3|08|45|E}}

| mouth_location = Loing

| mouth_coordinates = {{coord|48|20|09|N|2|46|56|E|display=inline,title}}

| progression = {{RLoing}}

| subdivision_type1 = Country

| subdivision_name1 = France

| length = {{convert|51.4|km|mi|abbr=on}}

| source1_elevation = {{convert|185|m|ft|abbr=on}}

| mouth_elevation = {{convert|50|m|ft|abbr=on}}

| discharge1_avg =

| basin_size =

}}

The Lunain ({{IPA|fr|lynɛ̃}}) is a {{convert|51.4|km|mi|abbr=on}} long river in the Yonne and Seine-et-Marne departments in north-central France. It is a right tributary of the Loing.{{sandre|id=F4380600|nom=Le Lunain}} Its source is in Yonne, less than {{convert|3|km|mi|abbr=on}} south-west of Égriselles-le-Bocage. It joins the Loing at Épisy in Seine-et-Marne.