Being a pluralist community, Nias consists of not Tionghoa (Chinese), Padang, Batak and Javanese. Social harmony within the community is like no other ever found in other regions across Indonesia. Indeed, social harmony amongst the Nias community has been a very much interesting social fact for research and analysis. Has some sort of local wisdom been exercised as a social capital to create the social harmony within the life of this religious-pluralist community? A research on this was conducted in Kota Gunungsitoli by applying the descriptive- qualitative research. The research shows that their local wisdom of Banua dan fatalitusota, Emali dome si so ba lala, ono luo na so yomo, Sebua ta ide'ide'o, side'ide'ide mutayaigo [tidak bold] and the fact that religious communities in this region have strong understanding and emphasis on their religious values. These factors heavily influence both the creation and the preservation of the social harmony within the community.