Ry or RY may mean:
- Ry Cooder
- Ry, Denmark
- Ry, Seine-Maritime, a municipality in France
- Rydberg constant, a unit of energy used in quantum physics related to the ground state energy of the hydrogen atom
- Rebel yell
- Railway
- Relay
- Ry (suffix), a Finnish suffix for a registered Non-profit organization
- RY (test signal), a character string used to test five-level teleprinter channels
- The stock symbol (tsx2 RY, nyse2 RY) for the Royal Bank of Canada
- Consolidated RY, a former cargo aircraft of the U.S. Navy