Abstract: Undisturbed soil core which has many macropores and disturbed soil core which has macropore (its diameter is known) are probed by CT.The theory of CT scanning is stated.CT scanning images are dealt with by using software photoshop and geographical information system software ARC/INFO and Mapinfo.The size, number, shape and continuity of macropores in transverse and vertical section of soil are characterized.The results indicate that CT scanning is a nondestructive method for characterizing macropores in soils, which is a promising method.