Abstract: Analyzing sentiments behind natural language processing is the focus of current research and the construction of sentiments lexicon is the foundation to analysis sentiments. This study was focused on domain features of sentiments tendency. By analyzing comprehensively available lexicons and introducing ontology technology, this resulted in a framework for the construction and automatic expansion of domain-oriented sentiment lexicon, which solved fundamental problems between the construction and automatic expansion of sentiments lexicon and the integration of lexicon application. The proposed framework reflected extremely fine characteristics of the domain feature. Experimental results showed that the proposed framework was effective in the automatic evaluation and layed a sound foundation for the domain-oriented sentiment tendency analysis.