Sexual minorities' use and appropriation of urban public space has received increasing attention in the research of social space. This line of research examines how sexual minorities practice particular urban space and how it is related to the production of meanings and the reconstruction of social relations. In the extant studies, it is commonly argued that sexual minorities' use of urban public spaces challenges the private/public divide in sexual norms and thus incubate emancipatory potentials. While this paper agrees with this point, it argues in the same time that the production sexual minorities' social space can also be constrained and conditioned by the entrenched structure of hetero-normativity as well as the socially constructed stigma of abnormality attached to sexual minorities. In particular, this paper pays attention to the fact that socially constructed stigma of abnormality can be internalized into sexual minorities' construction of self and subjectivity. Therefore, abnormality must be seen as a discursive construct which sexual minorities must constantly negotiate. This paper employs a case study of the gay cruising space in Park X, Guangzhou, in order to investigate gay men's participation in and experience of urban public space. It suggests that gay men's cruising space is saturated with rich social and cultural meanings. On the one hand, gay men's concentration in the cruising space and their various spatial practices are the outcomes of the established social and cultural structures which reify the rhetoric of the abnormality of homosexual identity. Thus gay men's appropriation of the cruising space in the park transgresses on the normative divide between the private and the public.