A traffic monitoring device, which comprises: an object information acquiring section including a detection block calculating unit that is adapted to acquire, with the use of distance information acquired for each image pixel obtained by imaging an object from above within a supervised sector that is divided into a plurality of three dimensional blocks above a two dimensional horizontal reference plane, detection blocks from the plurality of three dimensional blocks, the detection blocks being related to an object present within the supervised sector, a detection block (Bl) being acquired from the three dimensional blocks when the number of acquired image pixels in a block for which distance information is obtained, exceeds a threshold value that is set for that block and, which object information acquiring section is thereby operable to acquire a three dimensional object information; a block projected image generating unit that is adapted to generate a two dimensional block projected image, in which each pixel has height data as a pixel value, the two dimensional image being obtained by projecting the detection blocks onto the two dimensional horizontal reference plane; characterised in that the device further comprises: a template setting unit that is having a plurality of template blocks, the different template blocks corresponding to different sizes of heads and hairdos, wherein the template setting unit is adapted to set a template block that is corresponding to a shape of the object as present in the two dimensional block projected image, in which a block area containing a head reference (a) at a central portion of the block area, a shoulder reference (γ) along the peripheral edges of the block area and a hairdos buffer unit (β) that is separating the head reference (a) and the shoulder reference (γ) is used as a template image; a template matching unit that is adapted to perform a template matching with the two dimensional block projected image by means of the template block that is set by the template setting unit; and a determining unit that is adapted to determine the number of objects that is present in the supervised sector based on the template matching. an object information acquiring section including a detection block calculating unit that is adapted to acquire, with the use of distance information acquired for each image pixel obtained by imaging an object from above within a supervised sector that is divided into a plurality of three dimensional blocks above a two dimensional horizontal reference plane, detection blocks from the plurality of three dimensional blocks, the detection blocks being related to an object present within the supervised sector, a detection block (Bl) being acquired from the three dimensional blocks when the number of acquired image pixels in a block for which distance information is obtained, exceeds a threshold value that is set for that block and, which object information acquiring section is thereby operable to acquire a three dimensional object information; a block projected image generating unit that is adapted to generate a two dimensional block projected image, in which each pixel has height data as a pixel value, the two dimensional image being obtained by projecting the detection blocks onto the two dimensional horizontal reference plane; characterised in that the device further comprises: a template setting unit that is having a plurality of template blocks, the different template blocks corresponding to different sizes of heads and hairdos, wherein the template setting unit is adapted to set a template block that is corresponding to a shape of the object as present in the two dimensional block projected image, in which a block area containing a head reference (a) at a central portion of the block area, a shoulder reference (γ) along the peripheral edges of the block area and a hairdos buffer unit (β) that is separating the head reference (a) and the shoulder reference (γ) is used as a template image; a template matching unit that is adapted to perform a template matching with the two dimensional block projected image by means of the template block that is set by the template setting unit; and a determining unit that is adapted to determine the number of objects that is present in the supervised sector based on the template matching. a template setting unit that is having a plurality of template blocks, the different template blocks corresponding to different sizes of heads and hairdos, wherein the template setting unit is adapted to set a template block that is corresponding to a shape of the object as present in the two dimensional block projected image, in which a block area containing a head reference (a) at a central portion of the block area, a shoulder reference (γ) along the peripheral edges of the block area and a hairdos buffer unit (β) that is separating the head reference (a) and the shoulder reference (γ) is used as a template image; a template matching unit that is adapted to perform a template matching with the two dimensional block projected image by means of the template block that is set by the template setting unit; and a determining unit that is adapted to determine the number of objects that is present in the supervised sector based on the template matching.