Melissa officinalis L. (family Lamiaceae) is a perennial herbaceous plant naturally found in southern Europe and central Asia, with worldwide culinary and medicinal applications. It shows an erect, quadrangular stem that grows up to 1.5 m in height, carrying simple ovate to cordate leaves in an opposite decussate pattern. Microscopically, M. officinalis is generally characterized by anomocytic stomata as well as a variety of non-glandular and glandular trichomes, exemplified by labiaceous and capitate hairs; giving the plant a hairy texture and distinctive lemon-like scent thanks to the considerable secretion of volatiles from the latter hair types. Additionally, different tissues of this herb are generally devoid of calcium oxalate crystals. As part of our ongoing phytochemical and botanical research on M. officinalis, which previously included the detailed macroscopical and microscopical analysis of its leaves, the present study describes the botanical features of stems and roots of M. officinalis. Such botanical data could be of value as standardized parameters for authentication purposes of this multipurpose plant species.