An impression tray for a local area comprising: a bottom portion formed as a gentle curved shape similar to an alveolar ridge shape and forming a flat surface with an approximately uniform width at a corresponding length to at least three continuous teeth of a patient, an outer wall which is provided upright from an outer side of a curve of the bottom portion and having aheight gradually reduced in one end side so as to come to the same height as the height of the bottom portion; an inner wall which is provided upright from an inner side of the curve of said bottom portion via a circular arc shaped portion while being inclined to a direction so that an upper end comes away from the bottom portion, and having its height gradually reduced in both end sides so as to come to the same height as the height of the bottom portion; and the impression tray being made of a plastic, wherein a rim having a height from of 0.01 to 1 mm is provided along each of upper ends of said outer wall and said inner wall for forming an undercut portion below the rim on a bottom portion side of said outer wall and said inner wall, respectively, wherein elongated through holes are formed in said outer wall and said inner wall, wherein each of said elongated through holes reaches the bottom portion from a portion just below the rim and has a width of 1.5 to 4.0 mm, wherein a distance between adjacent elongated through holes is from 2 to 5 times the width of the elongated through hole, and is uniform, wherein circular through holes are formed in said bottom portion and are positioned at the center of the distances of adjacent elongated through holes, which are provided in said outer wall and said inner wall, wherein each of said circular through holes has a diameter of 3 to 6 mm, and wherein elongated end portion side through holes each of which has a width of 1.0 to 3.0 mm and a length of 5 to 15 mm are provided vertically to an axial direction of the curve of said bottom portion, and each of said elongated end portion side through holes is provided in both ends of said bottom portion, is closer to an end portion of said bottom portion than a line which connects the bottom portion side end portions of the respective elongated through holes in said outer wall and said inner wall positioned in the closest side to the end portions of said outer wall and said inner wall. a bottom portion formed as a gentle curved shape similar to an alveolar ridge shape and forming a flat surface with an approximately uniform width at a corresponding length to at least three continuous teeth of a patient, an outer wall which is provided upright from an outer side of a curve of the bottom portion and having aheight gradually reduced in one end side so as to come to the same height as the height of the bottom portion; an inner wall which is provided upright from an inner side of the curve of said bottom portion via a circular arc shaped portion while being inclined to a direction so that an upper end comes away from the bottom portion, and having its height gradually reduced in both end sides so as to come to the same height as the height of the bottom portion; and the impression tray being made of a plastic, wherein a rim having a height from of 0.01 to 1 mm is provided along each of upper ends of said outer wall and said inner wall for forming an undercut portion below the rim on a bottom portion side of said outer wall and said inner wall, respectively, wherein elongated through holes are formed in said outer wall and said inner wall, wherein each of said elongated through holes reaches the bottom portion from a portion just below the rim and has a width of 1.5 to 4.0 mm, wherein a distance between adjacent elongated through holes is from 2 to 5 times the width of the elongated through hole, and is uniform, wherein circular through holes are formed in said bottom portion and are positioned at the center of the distances of adjacent elongated through holes, which are provided in said outer wall and said inner wall, wherein each of said circular through holes has a diameter of 3 to 6 mm, and wherein elongated end portion side through holes each of which has a width of 1.0 to 3.0 mm and a length of 5 to 15 mm are provided vertically to an axial direction of the curve of said bottom portion, and each of said elongated end portion side through holes is provided in both ends of said bottom portion, is closer to an end portion of said bottom portion than a line which connects the bottom portion side end portions of the respective elongated through holes in said outer wall and said inner wall positioned in the closest side to the end portions of said outer wall and said inner wall.