This dissertation is a comparative study of literary texts authored by sixteenth-century Italian women that treat female friendship across the genres of epistolary writing, lyric poetry, and heroic poetry. The primary works under consideration include the correspondence between Elisabetta Gonzaga (1471-1526) and Isabella d'Este (1474-1539), the lyric poems authored by women in Lodovico Domenichi's anthology Rime diverse d'alcune nobilissime et virtuosissime donne (1559), and Margherita Sarrocchi's heroic poem the Scanderbeide (1623). In addition to the long-standing classical and Christian notions of friendship that held strong in Renaissance Italy, the genres of epistolary writing, lyric poetry, and heroic poetry each had a distinct and mostly male literary tradition of friendship. The literary works in this study reveal the various ways early modern Italian women contributed to their respective genres, and moreover, to larger cultural discourses on friendship by inserting the female perspective and experience. Their writings not only illuminate their understandings and interpretations of female bonds but also demonstrate their use of writing to initiate and maintain friendships with other women. Chapter 1 looks at women's epistolary prose through the correspondence between two princesses who were sisters-in-law, Elisabetta Gonzaga, the duchess of Urbino, and Isabella d'Este, marchesa of Mantua. Focusing primarily on letters exchanged during the beginning years of their friendship, I show how the two noblewomen relied on letter writing to express and reciprocate sentiments of intimacy. Chapter 2 on the Rime diverse d'alcune nobilissime et virtuosissime donne, the first all-female lyric anthology edited by Lodovico Domenichi, analyzes the friendship poems-sonnet exchanges between women to celebrate and form literary friendships and single-authored lyric that depict women's bonds-present in the collection. Looking at these two types of lyric in tandem, I argue that Petrarchism authorized women's expressions and representations of female friendship. Chapter 3 focuses on the heroic poem of Margherita Sarrocchi (1560-1617). Drawing from her classical and Renaissance predecessors who in their heroic poems depict and highlight friendships between male warriors, Sarrocchi revises the tradition by portraying and celebrating the bond that develops between two of the poem's female protagonists, Rosmonda and Silveria. While much has been explored with respect to male friendship in Italian Renaissance literature, the topic of female friendship has remained mostly untouched. With this study, I therefore address this need to uncover women's discourses on friendship by providing alternative perspectives and new insights on a subject that was traditionally understood in male terms.