The invention relates to the digital television technology, solves the problem that the terminal equipment of the current digital television bilateral network must be embedded in a private decipher module, and provides a realization method of bilateral network digital television system. The technical scheme is as follows: firstly a digital television bilateral network operator establishes a digital television local system which comprises a database, a Java application program download server, a bidirectional gateway, a biconditional conditional access system, a digital copyright management system, a user management system, an electronic program guide system, a demand system and value added service systems, a Java safety device is arranged on the user terminal equipment, and the Java safety device and the Java application program are used to ensure the safety and application of the digital television bilateral network. The beneficial effect of the invention is that the realization method is convenient to develop and modify and is applicable to the bilateral digital television network.