This paper explores the functions of Chinese final particle ou in both TCU-final and non-TCU-final positions in medical advice-giving. Using Praat, we differentiated phonologically marked and unmarked ou and analyzed their functions in both doctor and patient speech. The findings suggest a difference in participants’ use of ou: while non-TCU-final ou occurs mainly in the patient speech to mark newsworthiness and call for the doctor’s attention, TCU-final ou occurs in both the doctor and the patient speech serving various functions. Most importantly, the paper provides a new understanding of the various functions of ou as interconnected to each other under its intrinsic discreet quality that facilitates relationship building in the selected conversational activity.