You can absolutely paint a porcelain sink! In fact, painting a porcelain sink is a great way to give it an updated look without having to replace the entire fixture. When painting a porcelain sink, it's important to use a high-quality enamel paint designed for ceramic surfaces. You'll also want to make sure you thoroughly clean and sand the surface of the sink before painting. Once your paint is dry, you can apply a clear sealer to protect your new finish.