In recent years, the loss of biodiversity in paddy field landscape has become very important issue. The purpose of this study is to determine the relationship between plant species diversity of paddy field landscape and land use pattern in landscape scale. We selected 9 study sites in the southern part of Nagano Prefecture. The study sites had 4 condition types that were mountainous non-consolidated area, mountainous consolidated area, urban non-consolidated area, and urban consolidated area. Each study sites were divided by the mesh of 25m square to select randomly survey points. And, the quadrates for vegetation survey were selected on the points of mesh intersection located in 5 land use types (paddy, fallow, levee, slope and road). Vegetation survey was carried out at 850 quadrates in each 1 m². As a result, the number of appearance species was 381. To determine environmental factors of plant community, we focused on landform, soil conditions and land use. As a hypothesis, it is expected that various types of plant community is distributed in mountainous non-consolidated area where include many variation of environmental condition and land use. For the meeting, we want to discuss the land use pattern that conserve plant species diversity highly in landscape scale.