Abstract: A C₁-C₁₂ PNA analysis method for source rock study is introduced.the method involved vacuum degasification under 90°-100°C.The condition of degasification is constant,and strictly controlled.The degassing rate is high,with no distortion for separaed components.The results is proved to be representative.Meanwhile C₁-C₅ calibration factors are determined under optimum condition.C₅-C₁₀⁺ PNA program of HP5880 GC is worked out by revision of the original C₁-C₁₂ PNA program.Thus,the full usage of the instrument is made.The method is effective for C₁-C₁₂ PNA component study.