Angiotensin converting enzyme 2 (ACE2) (EC:3.4.17.23) is a transmembrane protein which is considered as receptor for spike protein binding of novel coronavirus (SARS-CoV2). Since no specific medication is available to treat COVID-19, designing of new drug is important and essential. In this regard, in silico method plays an important role as it is rapid, cost effective, compared to the trial and error methods using experimental studies. Natural products are safe and easily available to treat coronavirus effected patients, in the present alarming situation. In this paper five phytochemicals which belong to flavonoid and anthraquinone subclass, selected as small molecules in molecular docking study of spike protein of SARS-CoV2 with its human receptor ACE2 molecule. From the detail analysis of their molecular binding site on spike protein binding site with its receptor, hesperidin, emodin and chrysin are selected as competent natural products from both Indian and Chinese medicinal plants, to treat COVID-19.