Taraxacum kok-saghyz, a rubber-producing plant with excellent potential, emerges as a viable substitute for rubber tree (Hevea brasiliensis). While natural rubber is a desirable material, conventional techniques for assessing rubber content have faced challenges in meeting practical production requirements. To address this issue, we have developed a pyrolysis-mass spectrometry (PY-MS) instrument for the quantitative evaluation of natural rubber (NR) content in rubber-producing plants. The derived standard curve equation, established through external standard calibration, demonstrates a correlation coefficient (R2) surpassing 0.99. The method exhibits commendable recovery rates (93.27%-107.83%), relative standard deviations (RSD≤ 3.39%), and a swift analysis time of merely 10 minutes per sample, thereby enabling accurate and efficient quantification of NR. This approach possesses significant potential for extensive utilization in the assessment of rubber content in rubber-producing plants other than TKS. The integration of pyrolysis-mass spectrometry for the identification of polymers with high molecular weight offers a valuable pathway for the examination of diverse polymers.