The present invention aims to provide a process for producing an aluminum titanate-based ceramics fired body wherein a cracking of a ceramics shaped body during a degreasing step is suppressed and also sufficient mechanical strength for handling is provided to the ceramics shaped body for such a case of the transfer from a degreasing step to a firing step. The present invention is a process for producing an aluminum titanate-based ceramics fired body comprising a shaping step of obtaining a ceramics shaped body by shaping a starting material mixture containing inorganic components including an aluminum source powder and a titanium source powder and organic components; a degreasing step for removing the organic components contained in the ceramics shaped body in atmosphere with an oxygen concentration of not higher than 0.1% and under the temperature condition that the highest temperature is not lower than 700° C. and not higher than 1100° C.; and a firing step for firing the ceramics shaped body under the temperature condition that the highest temperature is not lower than 1300° C.; in this order, wherein the atmosphere at a heating step to 1300° C. during the firing step has an oxygen concentration of not lower than 1% and not higher than 6%.