The construction of the oil and gas geochemical database is the basis of resource sharing, scientific management and macroscopic decision-making of oil and gas geochemical information, and also serves as the foundation of oil and gas geochemical data processing and anomaly appraisal. Having collected and recorded oil and gas geochemical data of the past tens of years, this system can accomplish the registration, management, browsing, retrieval, report forming and preprocessing of oil and gas geochemical data. This paper has described the structure, characteristics and functions of the oil and gas geochemical database, and dealt further with the quantification and computerization of oil and gas geochemical exploration. All this represents the new advances and new research level in the field of oil and gas geochemical database.