Digitalization of TV program becomes the trend. It is possible to provide broadband data service through DVB. The specifications about data broadcast of DVB are outlined in this paper. A detailed theoretical analysis is made on data carousels applied to data push-casting, and the software flow chart of the composition of MPEG-2 transport stream is also given. Data push-casting can provide better service than Internet for the local subscribers, and it is a good method to resolve the problems such as high cost, low speed of accessing Internet, and great investment of reforming HFC networks.