My dissertation examines elite men’s social practice and behavior through which they differentiated and expressed degrees of closeness from the third to the tenth centuries. This dissertation asserts that the boundaries of propriety and impropriety in etiquette were conditioned by gender ethics of separate spheres (man at the outer, woman inner) and degrees of relationships. This research points out that playing pivotal role in social networking is non-verbal communication, which conveys messages more than verbal, audible form of language and was influenced by the reconstruction of space. I focus on two specific types of coded behavior: elite men’s social practices which required the physical presence of elite women and exemptions from the code of etiquette as an expression of exceptional closeness between friends. This dissertation primarily uses five kinds of sources, including dynastic histories, intellectual critiques, romantic tales, Buddhist writings, and visual materials. I contend that medieval elite men manipulated the gender ethics of separate spheres for their own benefits. I also argue that informality could express intimacy only by mutual consent, in the absence of which such behavior would be regarded as offensive, or even lead to charges of irreverence. Moreover, I also look into the instrumental use of closeness in court politics. I argue that emperors considered closeness an essential element of ideal courtiership during the seventh and eighth centuries. As such, they saw any sign of excessive closeness between officials as threatening to the regime. Centering on elite men’s coded behavior and social connections, this dissertation sheds new light on the Chinese gender ethics of separate spheres, ritual and social norms, and identity politics in medieval Chinese society. This project thus crosses the fields of gender history, space, and intellectual history.