In this paper we present an EEG detection system, which is a low-cost, portable, popularization. It is realized the low cost, mass brain health examination through the mobile phone software and networking in the "cloud" of the EEG pattern recognition expert database. The main functions of the system include: (1) through the mobile phone to control the EEG data acquisition; (2) established the expert system database of EEG patterns; (3) the EEG patterns, connected to the Internet matching. The key technologies of portable EEG health examination expert system such as structured storage of EEG data, feature extraction, construction of knowledge database and pattern matching are also discussed and researched in the paper.