The field survey was conducted from April 2021–December 2021in Mettupalyam forest range of Coimbatore forest division which is an integral part of Nilgiris Biosphere Reserve. A systematic random sampling method with 60 sample plots of 20 × 20 m and 8 transect line survey at 0.2% sampling intensity were laid out in the study area which recorded 54 trees, 25 shrubs, 22 herbs and 22 grasses. The result revealed that the maximum dominance was observed in Atlantia monophylla (32.20), Lantana camara (43.02), Abutilon indicum (54.87) and Oplismenus burmanii (19.34%) and minimum in Glycosmis pentaphylla (12.32), Euphorbia heterophylla (2.18), Mimosa pudica (2.82) and Melinis repens (0.18%) in tree, shrubs, herbs and grass layer, respectively. Furthermore, the highest Shannon D index (H = 3.08) observed in tree layer, followed by grass layer (H = 2.76), herb layer (H = 2.28) and shrub later (H = 2.25) along with Simpson index also higher in grass layer (1-D = 0.92), tree layer (1-D = 0.91), herb layer (1-D = 0.86) and shrub layer (1-D = 0.84), respectively. This study involving the cataloguing of flora in Mettupalayam Reserve Forest is the pioneer work which provided scientific and baseline information for conservation of flora in the forested area.