Judith Shulman Weis (born May 29, 1941) is an American marine biologist. Her research and writing focuses on estuarine ecology and ecotoxicology, including the responses of salt marsh and brackish marsh organisms, populations and communities to stresses, particularly heavy metal contaminants, invasive species and parasites. She is also working to reduce the spread of microplastics in the environment and find solutions to protecting coastal marshes from sea level rise.