Nowadays, Tolbutamide, Metformin, Gliclazideetc that are highly preferred as anti-diabetic drugs are mainly sulfonylureas and biguanides which are known to cause various adverse effects [4]. Hence in the recent years medicinal plants have become a subject of interest for drug development owing to their phytochemical constituents and their therapeutic potential. In particular, the angiosperms are given more emphasis but the pteridophytes which are significant group of plant kingdom with 12000 species are not much studied for their antidiabetic activity. Adiantum philippense Linn is commonly known as 'Hanspadi' or 'Walking Maiden hair fern'. It is widely distributed in many parts of India and used as an ornamental plant. It is ethnomedicinally used in bleeding diseases, burning sensation, erysipelas, epileptic fits, dysentery, and elephantiasis [5]. It has been reported that the dried whole plant has been used as a medicine for bronchitis and cough [6]. Adiantum philippense is also reported to have anti-bacterial [7] and anti-fungal activity [8]. Adiantum capillus veneries, a fern of the same genus as that of Adiantum philippense Linn possess antidiabetic potential which is marketed with brand name "Avenca TM ". Belonging to the same genus and family of Pteridophytes, insufficient information was available regarding anti diabetic potential of Adiantum philippense Linn (Adiantum lunulatum Burm f.) which led us to investigate its antihyperglycemic potential on alloxan induced diabetic rats. Materials and Methods Collection and authentication The fern Adiantum philippense Linn (AP) was collected from ChandraprabhaVanrai, Dapoli in the Ratnagiri district of Maharashtra in the end of monsoon and was authenticated by Dr. P.