Renilla muelleri (also spelled R. mulleri or R. müilleri) is a species of sea pansy. It has been reported from the Gulf Coast of the United States, notably the Florida panhandle, but is also reported from the eastern coast of South America. It is thought to be a euryhaline littoral species, found to a depth of up to 150 meters.

The genome of R. muelleri was sequenced in 2019.

Williams, Gary C. "Index Pennatulacea Annotated Bibliography and Indexes of the Sea Pens (Coelenterata: Octocorallia) of the World 1469-1999". Proceedings of the California Academy of Sciences. 51 (2): 19–103.