The purpose of this study is to explore professional development in online teacher communities. For this purpose, Indischool, an online teacher community, was selected and Indischool teachers' professional development activities and its characteristics were investigated. Various methods were used to collect the data, including the observation of online activities in Indischool website, interviews with Indischool teachers, and gathering the artifacts made by Indischool teachers. The findings showed that professional development in Indischool online teacher community was distinctively different from the traditional approach. First of all, regarding the professional development activities, workshops were not popular with Indischool teachers, unlike the traditional approach. Instead, sharing the resources, collaborative problem solving, and moral support were the major professional development activities. The professional development in Indschool was collaborative, practical, immediate, and ongoing. Based on these findings, a community approach to professional development was discussed.