With the development of computer technology and the continuous popularization of the network, the development of network applications is becoming more and more common, so the development of network applications is particularly important. In this article, the knowledge of TCP/IP programming interface Java Socket under Android is introduced. The classification of sockets and the connection-oriented socket communication mechanism are introduced. The network WIFI is realized by Socket in Android environment. The basics of communication and how to create connection-oriented client/server (C/S) web applications based on Java Sockets. In summary, when creating a Java Socket-based web application, you need to write an application to both the server side and the client side.