This thesis is an ethnography of communication of Deaf people in Taiwan，Hong Kong，and Mainland China. The fieldwork for this thesis was conducted between 2010 to 2013. Taiwan，Hong Kong and Mainland China have different political and education systems，though Chinese and Mandarin are common languages. For Deaf people in the three places，however，they use very different sign languages. This thesis focuses on the distinctiveness of sign languages used in daily life and multiple channels of communication with the world Deaf people live in. It explores how different sense organs used determine differences in employing symbols in communication. It is found that use of vision is the most fundamental and universal shared feature of all sign languages. Previous discussion of indexicality in linguistic anthropology generally sees the use of sense organ as a constant in oral-audio communication. This thesis contributes to the study of indexicality in linguistic anthropology by arguing that indexicality relies on linkage between sense organs in sign languages. In addition，it notes that language ideology of oral-audio speech discriminates the Deaf. The ideology of oral-audio language devalues visual language. In addition to documenting the communication characteristics of Deaf people，this thesis also makes it possible to rethink what is language，and，based on that，to consider ways in which changes in policy and practice can be made to remove obstacles for Deaf communication caused by linguistic ideologies.