Objectives The objective was to investigate postpartum uterus involution by real-time ultrasonography and vaginal cytology in Van cats. Methods This study included 15 healthy Van cats belonging to the Van Cat Research Centre (Yuzuncu Yil University, Van, Turkey). Starting 24 h postpartum, ultrasonographic measurements were performed on the placental and interplacental uterine horn regions every day. Decreases in the diameters and uterine content were considered as criteria for uterine involution.