A visual pests diagnosis system development tools based on binary tree (abbreviation: knowledge system development tools) was developed by techniques of computer visualization, binary tree, XML database and reasoning. This tool combined tree knowledge expression with rule-based reasoning machine, proposed the knowledge acquisition and the reasoning technique based on binary tree, and solved the problem of knowledge acquisition used for pests diagnosis with an expert system development tools–CLIPS. The reasoning machine with stateless continuous reasoning technology can improve the efficiency of knowledge acquisition and system reasoning. In this article, we introduced the components and working principles of the pest diagnosis system development tools, and described its usage with a simple example.