Ultrasonographic appearance of the normal involution process of the porcine postpartum uterus was examined. Six, sows were used to determine the normal Ultrasonographic appearance of the involution postpartum uterus. Ultrasonographic examinations were performed daily from days one through eight, then on days 15 and 21 postpartum. Ultrasonographic the mean local uterine wall thickness was 12.00 mm on day one postpartum. By day 15 the mean total uterine wall thickness was about 7.21 mm and on day 21 postpartum the uterus was about 6.12 mm. From one day to five days postpartum, intraluminal contents were isoechoic to the endometrium. From 15 days to 21 days, the luminal 7ont7llts were of mixed echogenicity compared to the endometrillm.