Franciscus Adrianus "Frank" Ludewig (22 October 1863 – 16 September 1940) was a Dutch architect who lived and worked mostly in the United States.

Ludewig was born in Beverwijk, Netherlands, and studied architecture at the Polytechnical Institute in Delft where he befriended another future architect, Jacobus van Gils (1869–1919), whose sister Dorothea he married in 1896.

He built several houses, reconstructed Wijchen castle and restored churches in Beek, Leur and Rosmalen.

In the nineteen years of his American career, Ludewig built 21 churches and chapels, 11 schools and 10 presbyteries.

Ludewig retired at the age of 69 and, after suffering from heart ailment for 18 months, died in Grand Rapids, Michigan in 1940.