Introduction: Ailanthus altissima (Simaroubaceae) is a large tree indigenous to China. It is known as the “Tree of Heaven”, used in traditional medicine in many parts of Asia, including China to treat cold, gastric diseases, diarrhea and endoparasites. It is also used as a bitter aromatic drug and as an antitumoral. Objective: The present study deals with comparative pharmacognostical parameters for the bark of stem and root of Ailanthus altissima, Mill. Swingle. Materials and Methods: The stem and root bark were collected, shade dried and powdered plant material was studied for its proximate values by standard methods. The extracts were subjected to a preliminary phytochemical screening for the detection of various phytoconstituents. Results: Proximate analysis revealed that the dry plant powder of stem bark has 6.48 % total ash, 0.42% acid insoluble ash, 4.60 % water soluble ash and for root bark 7.22 % total ash, 0.74% acid insoluble ash, 5.98 % water soluble ash. The Loss on drying for stem and root bark were found out to be 6.62 % and 10.46 % respectively. The stem and root bark of plant powder were found to possess phytoconstituents. Fluorescence analysis revealed the behaviour of the plant powder when treated with different chemical reagents. Conclusion: The present study reveals the preliminary phytochemical and proximate analysis of stem and root bark of Ailanthus altissima. Information obtained from these studies can be used as markers in the identification and standardization of this plant as a herbal remedy and also towards monograph development on the plant.