The invention provides an impression tray for an upper jaw which is made of a plastic, can prevent a set impression material from floating upward from the tray and being peeled off from the tray, and can be used for taking an impression having a high precision. The impression tray has an outer wall (2), a bottom portion (1) forming a flat U-shaped surface with an approximately uniform width and a bulge portion (3) occluding the inner side space between the U-like shaped bottom portions (1). A rim (4) is provided along the upper end of the outer wall (2). Elongated through holes (5) extend vertically from just below the rim (4) to the bottom portion (1) in the outer wall (2). The distance between adjacent through holes is 2 to 5 times the width of said elongate through holes (5). Similar elongated through holes (6) are provided in the bulge portion (3). Circular through holes (7) and elongated through holes (8) are provided in the bottom portion (1).
