Nelly Aronowsky (15 July 1892 – September 1966), known professionally as Nelly Arno, was a German-born British theatre, film and radio actress.

Aronowsky was born in Karlsruhe to Abraham Aronowsky and Fanny (née Maysel). She had a younger brother, Alexander, born in 1896.

In 1920, she was living in Bernburg and already using the stage name Arno. She was appearing on the English stage and radio productions following the Second World War. It's not apparent when she emigrated, but she became a British citizen in 1948.

She died in Queens, New York in September 1966.