Marmaton River

{{for|the battle|Battle of Marmiton River}}

{{Use American English|date=February 2025}}

{{Infobox river

| name = Marmaton River

| native_name =

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| image = Marmaton River.jpg

| image_size =

| image_caption = The Marmaton River near Nevada, Missouri

| map = Osagerivermap.png

| map_size =

| map_caption = Map of the Osage River watershed including the Marmaton River

| pushpin_map =

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| subdivision_type1 = Country

| subdivision_name1 = United States

| subdivision_type2 = State

| subdivision_name2 = Kansas, Missouri

| subdivision_type3 =

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| length = {{convert|102|mi|km|abbr=on}}

| width_min =

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| discharge1_location= USGS 06918060 near Nevada, MO{{cite web | title = Water-Data Report 2013 - 06918060 Marmaton River near Nevada, MO | publisher = U.S. Geological Survey | url = http://wdr.water.usgs.gov/wy2013/pdfs/06918060.2013.pdf | accessdate = 2015-11-05}}

| discharge1_min = {{convert|0.03|cuft/s|m3/s|abbr=on}}

| discharge1_avg = {{convert|1051|cuft/s|m3/s|abbr=on}}

| discharge1_max = {{convert|33800|cuft/s|m3/s|abbr=on}}

| source1 =

| source1_location = Allen County, Kansas

| source1_coordinates= {{coord|37|56|45|N|95|07|51|W|display=inline}}

| source1_elevation = {{convert|1105|ft|abbr=on}}

| mouth = Little Osage River

| mouth_location = Vernon County, Missouri

| mouth_coordinates = {{coord|37|59|57|N|94|19|08|W|display=inline,title}}{{cite gnis | 721891 | Marmaton River | 2014-11-05}}

| mouth_elevation = {{convert|732|ft|abbr=on}}

| progression =

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| custom_label = Watersheds

| custom_data = Marmaton-Little Osage-Osage-Missouri-Mississippi

| extra =

}}

The Marmaton River (MAR-muh-tuhn) is a {{convert|102|mi|km|adj=mid|-long}}U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. [http://viewer.nationalmap.gov/viewer/ The National Map] {{webarchive|url=https://web.archive.org/web/20120329155652/http://viewer.nationalmap.gov/viewer/ |date=2012-03-29 }}, accessed May 31, 2011 tributary of the Little Osage River in southeastern Kansas and western Missouri in the United States. Via the Little Osage, Osage and Missouri rivers, it is part of the watershed of the Mississippi River.