In the semantic web context,the formal representation of knowledge is not resourceful while the informal one with uncertainty prevails. In order to provide an uncertainty reasoning service for semantic web applications, we propose a probabilistic extension of Description Logic, namely Probabilistic Description Logic Program (PDLP). In this paper, we introduce the syntax and intensional semantics of PDLP, and present a fast reasoning algorithm making use of Logic Programming techniques. This extension is expressive, lightweight, and intuitive. Based on this extension, we implement a PDLP reasoner, and apply it into practical use: Tourism Ontology Uncertainty Reasoning system (TOUR). The TOUR system uses PDLP reasoner to make favorite travel plans on top of an integrated tourism ontology, which describes travel cites and services with their evaluation.