Adhatoda vasica is a medicinally important perennial shrub used in traditional as well as modern systems of medicines to treat cough and cold, asthma, dysentery, rheumatic pain and many other disorders. A severe leaf spot disease was observed on A. vasica leaves collected from different regions of Bilaspur, Himachal Pradesh, India. The disease was further investigated and the pathogen was identified in the present study. Small necrotic lesions on leaves which later developed in to circular light to dark grey spots were observed when disease started. New dark grey spots encircled the older one by giving concentric ring appearance along with leaf shrinkage around the necrotic spots were also recorded. Hyaline, straight, dumbbell shaped, aseptate and oblong or cylindrical conidia with rounded or bulbous ends having size ranging between 10.4-18.6×3.4-5.5 μm and brown coloured setae of 25-130 × 3-5 μm size were observed during microscopy. Colletotrichum gloeosporioides was identified as the causal agent based on disease symptoms, the morphological and microscopic characteristics of the isolated fungus and pathogenicity tests. To our knowledge, this is the first report of C. gloeosporioides on leaves of A. vasica in India.