Ralph Maxwell Lewis (February 14, 1904 – January 12, 1987), was an American mystic and the second Imperator of the Rosicrucian organisation AMORC from 1939 to 1987.

On August 2, 1939, he was elected by the Board of Directors of the Supreme Grand Lodge of AMORC as Imperator of the order, a position he held until his Great Initiation on January 12, 1987.

In March 1940, Lewis was elected President of the International Supreme Council of the order Rosæ Crucis.

Among the awards he received in his lifetime was the honorary degree of doctor of literature from Andhra University in India,[citation needed] and the star and the cross of science from the International Academic Council.

[citation needed] He founded the Grand Lodge of Brazil in the summer of 1956, and he commissioned new buildings for the Rosicrucian Egyptian Museum in 1966.