Objective To observe the effects of a visceral hypersensitivity model in rats with irritable bowel syndrome established by neonatal maternal separation combined with colorectal distension and drugs with chronic stress, and to discuss their features. Methods Two-day-old and two-month-old Sprague-Dawley rats were randomly divided into CRD, control, and CUMS groups. After establishing the model, the general conditions, stools, visceral sensitivity, and anxiety-depression-like behavioral changes were evaluated. Colonic tissue was obtained for pathological examination. Results Both model groups had a higher AWR score, lower visceral pain threshold, and changed fecal characteristics and water content. The CUMS group had a shorter open arm residence time of the elevated plus maze test and shorter total distance and central area residence time of the open field test. Conclusions Both models showed visceral hypersensitivity and fecal changes, which agreed with the clinical symptoms of IBS, and are more inclined to the diarrhea type. Additionally, the CUMS group model had emotional changes.