Disclosed are: a columnar aluminum titanate which is capable of providing a sintered body that has low thermal expansion coefficient, large pore diameter and high mechanical strength; a method for producing the columnar aluminum titanate; and a sintered body of the columnar aluminum titanate. Specifically disclosed is a columnar aluminum titanate which is characterized in that the average aspect ratio (= number average length/number average breadth) is 1.5 or more and the magnesium content is preferably within the range of 0.5-2.0% by weight relative to the total of titanium and aluminum in terms of oxides.