A cDNA encoding mouse intestinal trefoil factor (mITF) was successfully cloned and sequenced from the small intestine of C57BL/6 mouse by using the combination of reverse transcription-PCR and rapid amplification of cDNA ends methods. The gene was, similar to rat and human ITFs, mainly expressed in the small and large intestine. The mITF expression was up-regulated during the recovery phase after depletion of goblet cells in acetic acid-induced colitis. On the other hand, the expression in the jejunum was not altered, while goblet cell hyperplasia was induced by Nippostrongylus brasiliensis infection. These results suggest that the mITF expression did not simply correlate with the number of goblet cells. The mITF may play an important role in the maintenance and repair of mucosal function of the rectum. Additionally, the mITF in the jejunum may play a role in alteration of the physicochemical nature of goblet cell mucins, thereby affecting the establishment of intestinal helminths.