Lake Tatawai was a tidal freshwater lake located immediately north of Lake Waipori in Otago, in New Zealand's South Island.^[1]

It is one of the historical lakes that was drained soon after European Settlement of the Taieri Plains. Lake Tatawai drained into Lake Waipori by a small channel, and ultimately into the Taieri. It was a very shallow lake and would have originally been surrounded by wetlands.