To provide an unmanned transportation system in which a running direction of an unmanned carrier can be controlled even when the unmanned carrier itself cannot identify a forward direction and a backward direction.

An unmanned transportation system 1A includes a guide line 2A and an unmanned carrier 3A. The guide line 2A includes a plurality of colored areas 2a₁ and 2a₂. The unmanned carrier 3A includes: imaging means 4 which continuously generates image data of an area including the guide line 2A; a color identifying part 5A which draws a virtual line parallel with the guide line 2A on the guide line 2A included in the image data and identifies a color of the colored areas 2a₁ and 2a₂ at a front end part or a rear end part of the virtual line; and a running direction identifying part 6A which identifies whether the unmanned carrier runs along a first direction or a second direction, in accordance with whether a length of the virtual line within the colored areas 2a₁ and 2a₂ colored in the color identified by the color identifying part 5A, in one piece of image data is increased or reduced in another piece of image data generated after the one piece of image data.