Fistula in anorectal region is an abnormal communication between anal canal and rectum. It is occur due to persistent anal gland infection results in anorectal abscesses which rupture inside as well as outside resulting in fistula.Bhagandara described in ayurveda can be correlated with fistula in ano.The chances of recurrence in different types of anal fistulae range between 7% to 50% .Foreign body is one of the main reason for recurrence of fistula. Ayurveda text also described Agantuj shalya as a causative factor of Bhagandara. Sushrutacharya described Ksharsutra as an important surgical process for treatment of Bhagandara .A single case study is undertaken to evaluate the examination of presence of foreign body as a causative factor for recurrence of fistula. During surgical procedure foreign body i.e. watermelon seed found in the track of fistula. After removal of this Agantuj shalya and Ksharsutra setting patient showed significant rapid healing and non occurrence of fistula. Hence during surgical process of fistula in ano in each patient examination of fistula tract and its periphery for foreign material is essential.