A new and distinct Hosta plant named ‘Sun Mouse’ with leaves that are slightly wavy thick substance and with golden coloration that holds up well through the season. The flowers are dark lavender bells tightly congested just above the foliage on chartreuse scapes with red blushing near base. ‘Sun Mouse’ has excellent vigor with rapid production of divisions, and its compact habit makes it useful in the miniature garden, as edging or front of the landscape border, in containers, as a specimen or en masse.
