This study is a qualitative study in order to to analyze female masculinity Kak Ros in the story of comic Upin-Ipin. The theory used in this paper is female masculinity by Halberstam (1998) and Lehman (2001). Female masculinity in Halberstam’s study is assuming that sex determines men and women, while masculinity and femininity are viewed as social constructs influenced by roles, personality traits, and life experiences. There were found three characteristics of Kak Ros that implemented female masculinity according to Halberstam (1998): butch realness, femme pretender, and male mimicry. While the implementation of Kak Ros female masculinity according to Lehman (2001) are power and leadership. Different social conditions that Kak Ros face in the family make a significant contribution to gender identity by constructing and deconstructing gender identities.