The Shaiji, a religio-cultural community of southwestern Bangladesh, have an indigenous medication system using locally grown plants. A total of 36 individuals were interviewed using questionnaire. The Shaiji, living in the interior or near bushy habitats for the sake of meditation and other spiritual activities, were found to be totally dependent on herbal medicines for treating ailments ranging from casual cold to diabetes. As this indigenous knowledge is handed down orally from generation to generation, there is a great possibility that the knowledge will be lost over time. A total of 47 plant species were used by the Shaiji for medicinal purposes. They mainly used leaves, either taken orally or used externally. They used the plant species in a sustainable manner and also cultivated some. Thus, they play an important role in biodiversity conservation.