Kattampally wetland is a large swamp on the floodplains of the Valapattanam River in Kannur District of Kerala previously nominated as a Ramsar site. By systemic sampling in different seasons and sites within the wetland, we recorded the diversity of adult odonates. The area was found to be rich in odonate diversity with greater species richness than other wetlands in Kerala. We found a total of 66 species of odonates from 42 genera including four species endemic to the Western Ghats, namely: Ceriagrion chromothorax, Caconeura cf. risi, Pseudagrion indicum, and Platylestes kirani. Land usage and habitat alteration were found to be the main threats to odonate diversity. National and international recognition for the wetland would help in future conservation of the site and its biodiversity.