Mecodema is a genus of large flightless ground beetle (Carabidae) endemic to New Zealand. The genus is very diverse in comparison to the other three New Zealand genera (Diglymma, Oregus, Orthoglymma) within the subtribe Nothobroscina (tribe Broscini). Mecodema is geographically widespread across both the North and South Islands, as well as numerous offshore islands, including the Three Kings Is., Poor Knights Is., Aotea (Great Barrier Is.) and Hauturu (Little Barrier Is.), Kapiti Is., Stephens Is., Stewart Is., Chatham Is., Snares Is.