Pipelines are regarded as one of the most practical and economical modes for transporting dangerous and combustible substances, such as oil and gas. However, the use of historical failure data in qualitative risk assessment of oil and gas pipelines is unusual due to lack of data or incomplete information. The pipeline incident database (PID) provides valuable information for researchers to identify potential threats of oil and gas pipeline systems, and catty out effective risk assessment. In this study, pipeline failure statistics such as pipeline classifications, incident definitions, failure causes and failure frequencies from the United States, Canada, Europe and United Kingdom are compared. Failure frequency of oil and gas pipelines for different kinds of primary failure causes are estimated from the statistical analysis of the mileage, pipe-related incident, and failure cause data collected by each PID. Although above-mentioned databases are established by pipeline operators in developed countries, the statistical analyses of incidents on oil and gas pipelines based on comparing different pipeline incident databases can benefit the quantitative risk assessment of pipeline systems also in some developing countries where pipeline incident database haven’t been established.