Teacher preparation is a process of instructional fulfillment in teacher education. This program is widely used in school that need professionalism in terms of networking. Supervisor take their role to support preservice teacher in many expected attributes which school workers should be known and learned in various kind of school contexts. This study aims to investigate the implementation of professional experiences through online reflection in teacher preparation program. The study divided into 3 phases: analyze criteria relevant to professional experience, develop online reflection, implement how online react with preservice teachers. Two hundred and thirty nine preservice teachers in seven majors of Mahasarakham University, enrolled in Professional Experiences I, academic year 2010 in which provide their expression about professional experiences through online reflection. Data were collected by questionnaire and supporting interview. This study revealed that professional experiences can enable preservice teachers to remain connected to peers and university supervisors. However, it did not reach some preservice teachers who those no need internet and also some criteria relevant to time at online was limited due to lots of responsibilities to do in school hours. Financial support was provided by the Faculty of Education, Mahasarakham University. (Contains 1 table.)