Extracting data from Web pages using wrappers is a fundamental problem arising in a large variety of applications of vast practical interest. In this paper, we propose a novel schema-guided approach to wrapper generation. We provide a user-friendly interface that allows users to define the schema of the data to be extracted, and specifies mappings from a HTML page to the target schema. Based on the mappings, the system can automatically generate an extraction rule to extract data from the page. Our approach to wrapper generation can significantly reduce the work of human beings in this process. And the user never have to deal with the internal extraction rule, or even familiarity with the details of HTML.