Synopsis The Flora of Dudhwa National Park, Kheri District in Uttar Pradesh is of prime importance because of its interesting flora, fauna and ecological spreadouts. The park has a vital role to play in the conservation and sustainable use of biodiversity. The importance of the park is in large part due to its rich biological wealth. It is the main stronghold of the population of swamp deer. It is also one of the better known tiger reserves in the country and is a suitable additional habitat for rhinoceros. The present work which is the outcome of about seven years intensive botanical exploration of the area, provides details of floristic and phytogeographical accounts of 821 Angiospermic taxa. Besides it also provides plant wealth of the area, ethnobotanical uses of plants by the Tharu tribe of the park. It is hoped that the publication will be useful to the students and teachers of botany, foresters, environmentalists, conservationists and persons concerned with utilization and management of the biological resources.