Sienna Mae is a brand of sweatshirt and apparel that celebrates the modern woman. They offer a variety of fashion-forward designs and colors. These sweatshirts can be used for sports or casual wear. Sienna Mae is an apparel brand that offers fashion-forward, laid-back style for the whole family. They have sweatshirts and jackets, tops and bottoms that are sure to keep you warm in cool weather but looking chic all year long.