The term `Runway incursion` is any occurrence at an aerodrome involving the incorrect presence of an aircraft, vehicle or person on the protected area of a surface, designated for the landing and take-off of aircraft. Runway incursion results from several hazards which refers to potential risks or factors that can cause damages to human lives, health, properties or environments. This study is to identify hazards causing runway incursion using Preliminary Hazard Analysis and reviewing ICAO documentation and FAA Runway Safety Report, and then to categorize the hazards into three types: ATC controller deviations, pilot/vehicle deviations and airport design factors. In addition, this study analyses the weight of each hazard with Analytic Hierarchy Process and gives more information to airport operators about the hazards when they make risk mitigation schemes as the results.