It is of great interest and importance to have a comprehensive understanding of the characteristics of tar derived from major components of municipal solid waste to guide gasification syngas cleaning and upgrading. In this paper, cellulose and polyvinyl chloride (PVC) were chosen as principle components, and the surface tension, kinematic viscosity, and contact angle of tar derived from cellulose, PVC, and their mixture at temperatures of 400, 500, and 600 °C were experimentally studied. Gas chromatography−mass spectrometry (GC−MS) and 13 C nuclear magnetic resonance (NMR) were employed to identify major tar species and their corresponding molecular bonds. Results indicated that the surface tension increased from around 51.4, 41.4, and 58.6 mN/m at 400 °C to 54.8, 47.2, and 64.9 mN/m at 600 °C for cellulose, PVC, and their mixture, respectively. Correspondingly, the kinematic viscosity changed from around 5. 64, 20.37, and 10.37 cSt to 10.35, 34.21,and 15.51 cSt. The surface tension was affected by the co-pyrolysis of cellulose and PVC, while no obvious interaction was observed for kinematic viscosity. GC−MS results showed that the major species of tar generated from cellulose were miscellaneous hydrocarbons with a proportion between 69.7 and 96.3%. The composition for tar derived from PVC and their mixture showed a dramatic difference compared to that from cellulose. NMR spectra indicated that the function group of tar derived from the PVC and cellulose mixture was dominated by PVC.