Abstract: Fast pyrolysis has obvious advantages in producing energy products and reducing environmental pollution,so it is regarded as anexcellent medical waste treatment technology. The characterization method of GC-MS coupled with LC-HRMS was used to supplement thedetection blank of components with high boiling point in pyrolysis oil of medical waste,and the component characteristics and variationrules of pyrolysis products of typical medical waste were accurately revealed. It is found that the pyrolysis of cotton sticks mainly producespyrolysis oil and char,with yields of about 40%. The pyrolysis gas is mainly composed of CO and CO2,and the main components of oil arealdehydes,ketones,acids and phenols. The characteristic components of oil are sorbic acid and 3(4hydroxy3methoxyphenyl) propionicacid. With the increase of temperature,the components such as CO,H2,CH4,aldehydes,ketones and acids gradually increase,while phenols gradually decrease. The surface functional groups or structures of cotton sticks pyrolysis char include —OH,—CHx,C