Nathan Lee Chasing His Horse (born April 28, 1976), also known as Nathan Chasing Horse and Nathan Chases His Horse, is a Sicangu Lakota actor.

Chasing Horse portrayed the young Lakota character Smiles a Lot in Kevin Costner's 1990 film Dances with Wolves. He has appeared in three TNT telefilms with First Nations actor Eric Schweig: The Broken Chain, Into the West, and Bury My Heart at Wounded Knee.