Mullayar

{{Short description|River in India}}

{{Use dmy dates|date=August 2019}}

{{More citations needed|date=February 2013}}

{{Infobox river

| name = Mullayar

| native_name = {{native name|ml|മുല്ലയാർ}}

| image =

| image_caption = Location map of the Mullayar River

| source1_location = Kottamalai peak in the Periyar Tiger Reserve

| mouth_location = Periyar at Mullakudy

| subdivision_type1 = Country

| subdivision_name1 = India

| length =

| source1_elevation =

| discharge1_avg =

| basin_size =

}}

Mullayar River is a tributary of the Periyar River, the longest river in Kerala. It originates at Kottamalai peak {{cite web |url=http://shodhganga.inflibnet.ac.in/bitstream/10603/423/11/11_chapter2.pdf |title=Study Area and Methods}} in the Periyar Tiger Reserve. The Mullayar flows west through the reserve {{cite web |url=http://www.periyartigerreserve.org/maps/Drainage.jpg |title= Periyar Tiger Reserve drainage }} and joins the Periyar at Mullakudy just at the beginning of the Periyar lake formed by the Mullaperiyar dam.