Keyword search in relational databases has recently emerged as a new research topic. As a search result is often assembled from multiple relational tables, existing IR-style ranking strategies can not be applied directly. In this paper, we propose a novel IR ranking strategy considering query semantics for effective keyword search. The experimental results on a large-scale real database demonstrate that our method results in significant improvement in terms of retrieval effectiveness as compared to previous ranking strategies. Key words: top-k,keyword search,effective,relational database