A device and a method for manufacturing a three-dimensional object (3) by solidifying layers (25) of a material in powder form at those positions corresponding to the respective cross-section of the object (3) are provided. The device comprises an application device (40) for applying layers of the material in powder form (47) in the building area (5), which can be moved over the building area (5). The application device (40) is formed to have a first longitudinal wall (41a) and a second longitudinal wall (41b) that are connected to one another via two side walls. The application device (40) is provided with a fluidization device for homogenizing the material in powder form (47). This fluidization device comprises at least one hollow body having escape openings in its walls, through which escape opening a gas can flow from the hollow body into the material in powder form (47).