Compared with traditional classroom teaching mode with lots of drawbacks, web-based instruction meets students’ requirements in autonomous learning, exploration, cooperation, individualized learning with promising help for classroom teaching. A design of web-based instruction of College Computer Introduction in packaging specialty is proposed and the practice is performed in following aspects. A platform is constructed as the basis of web-based instruction. The education emphasis is recognized by distinguishing knowledge levels. Customized instruction programs are designed in accordance with students’ autonomous learning. Topic discussion and web-based question answering are involved in the platform to enhance communication and pertinent counseling. The resources are updatable and online test can help the self-evaluation. The practice proves that web-based instruction is profitably compatible and complementary with traditional teaching mode.