Uarini River

{{Infobox river

| name = Uarini River

| native_name ={{native name|pt|Rio Uarini}}

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| pushpin_map = Brazil

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| river_system = Solimões River

| progression =

| source1_location = Amazonas state

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| mouth_location = Uarini, Amazonas

| mouth_coordinates = {{coord|-2.981858|-65.110090|display=inline,title}}

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| subdivision_type1 = Country

| subdivision_name1 = Brazil

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| tributaries_left =

| tributaries_right = Copacá River

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The Uarini River ({{langx|pt|Rio Uarini}}) is a river of Amazonas state in north-western Brazil.

It is a tributary of the Solimões River.

The Uarini River flows north through the {{convert|187982|ha}} Baixo Juruá Extractive Reserve, created in 2001.{{citation|ref={{harvid|RESEX do Baixo Juruá – ISA}}|language=Portuguese

|title=RESEX do Baixo Juruá|publisher=ISA: Instituto Socioambiental

|url=https://uc.socioambiental.org/uc/1151|accessdate=2016-10-22}}

It then flows in a roughly northeast direction, entering the Solimões near the town of Uarini.