CSI Diocese Cochin (Former North Kerala Diocese) is one of the twenty-four diocese of the Church of south India (commonly referred to as CSI, successor of the Church of England and other protestant church missions in India). The diocese of North Kerala came into existence with the inauguration of the CSI, comprising of Trichur district of the former Travencore-Cochin Dioceses and the former Malabar Basel Evangelical Mission Church of the SIUC. Area –wise the Diocese was spread over nine Districts-Kasargod, Kannur, Kozhikode, Wayanad, Malappuram, Palakkad, Trichur, Ernakulum and a part of Idukki revenue districts consisting of plantation areas of Munnar.
After a long discussion in the Diocese and the Synod level, the CSI North Kerala Diocese was bifurcated into two Dioceses as CSI Cochin Diocese and CSI Malabar Diocese. Cochin Diocese become a diocese on the September 2015 and it remained as the mother diocese. So, this diocese named as CSI Cochin Diocese and it is the former CSI NKD. The former diocesan office of the CSI NKD continues as the Diocesan office of the CSI Cochin Diocese. The present bishop of Cochin Diocese is Rt. Rev. B. N. Fenn, who was the last bishop of CSI NKD before its bifurcation.