The Knesset Eliyahoo, also Knesset Eliyahu, is an Orthodox Jewish synagogue located in downtown Mumbai, India. It is the city's second oldest Sephardic synagogue. It was established in 1884 by Jacob Elias Sassoon, son of Eliyahoo David Sassoon and grandson of David Sassoon; the latter had immigrated from Baghdad to India in 1832 due to persecution and had settled in Mumbai, then known as Bombay. It is maintained by the Jacob Sassoon Trust. The building's significance is attributed to its Jewish traditions as well as Indian and English colonial influences.

David Sassoon was the treasurer of Baghdad between 1817 and 1829. He became the leader of the Jewish community in Mumbai after Baghdadi Jews emigrated there.