The Diocese of Tirunelveli is one among the 24 dioceses of the Church of South India (CSI).It is based at Tirunelveli, in the state of Tamil Nadu, southern India. The diocese has 687 churches, 101 pastors, and a membership of 1,86,000.Holy Trinity Cathedral, at Palayamkottai is the Cathedral of Tirunelveli Diocese. The churches were established by church missionary society (CMS) missionaries and Society for propagating gospel (SPG) missionaries. In the year of 1919 Tinnevely Diocese Trust Association (TDTA)was formed by uniting both mission and also with baptists and presbyterians churches in the neighbourhood.