Oybach
{{short description|River in Germany}}
{{Expand German|topic=geo|date=September 2011|Oybach}}
{{Infobox river
| name = Oybach
| image = OybachWinter2006.jpg
| image_size =
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| image_caption = The Oybach near Gruben (a parish of Oberstdorf)
| map =
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| source1_location =
| mouth_location = Trettach
| mouth_coordinates = {{coord|47.3914|N|10.2936|E|source:wikidata-and-enwiki-cat-tree_region:DE|display=it}}
| progression = Trettach→ {{RIller}}
| subdivision_type1 = Country
| subdivision_name1 = Germany
| subdivision_type2 = State
| subdivision_name2 = Bavaria
| length = {{convert|10.2|km|abbr=on}}{{GeoQuelle|DE-BY|GV}}
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The Oybach is a river of Bavaria, Germany. It flows into the Trettach south of Oberstdorf.