Abstract: Ethnobotanical investigation of traditional medicinal plants used by the Santal community at Sadar Upazila of Chapai Nawabganj district, Bangladesh was recorded. Frequent field trips were made during December 2013 to June 2015 to record ethnobotanical data by interviewing Santal people of various age groups, mostly ranging between 22 to 84 years, including medicinal healers (herbalists/hakims). A total of 151 plant species under 131 genera and 64 families have been documented which are used for the treatment of 102 categories aliments/diseases. For each species scientific name, local name, habit, family, ailments to be treated, mode of treatment and part(s) used are provided. It was observed that the availability of these plants was decreasing at an alarming rate. This observation also reveals that habitat destruction, over exploitation and unplanned agriculture were the reasons for depletion of medicinal plants. Therefore, the medicinal plants are used as traditional healthcare system need urgent conservation.