Reticulon 4 receptor (RTN4R) also known as Nogo-66 Receptor (NgR) or Nogo receptor 1 is a protein which in humans is encoded by the RTN4R gene.

This gene encodes the receptor for reticulon 4, oligodendrocytemyelin glycoprotein and myelin-associated glycoprotein. This receptor mediates axonal growth inhibition and may play a role in regulating Axon regeneration and plasticity in the adult central nervous system.