Abstract: To effectively provide diagnosing and treatment of pig disease for culturists, the expert system for diagnosing and treatment of pig diseases was developed with PAID4.0, which is an all-purposed platform for agricultural expert system development. The system has the main functions of providing a disease treatment technique by describing the disease on line through the Internet, including more than 70 varieties of pig diseases and 140 correlative pictures, and application of the system are also discussed on the paper.