Steam huff and puff is an important development method for heavy oil reservoirs. An accurate description of the remaining oil distribution after steam huff and puff is crucial for reservoir development. In this study, an experimental setup is used to simulate the multi-cycle steam huff and puff process more realistically. The occurrence state and distribution of remaining oil after different cycles of steam huff and puff are investigated. CT scanning is conducted after the first, fourth, and seventh cycles. Based on characterization parameters such as shape factor, contact ratio, and Euler number, the microscopic remaining oil is classified into network remaining oil, cluster remaining oil, film remaining oil, and isolated droplet remaining oil. The volume proportions of different types of remaining oil of different cycles of steam huff and puff are compared. The results indicate that as the number of cycles increases, the volume proportion of network remaining oil decreases, while the volume proportions of cluster, film, and isolated droplet remaining oil increase. From the first to the seventh cycle, the volume proportion of network remaining oil decreases by 34.11%, while the volume proportions of cluster, film, and isolated droplet remaining oil increase by 12.87%, 14.48%, and 6.76% respectively. The oil phase transitions from a continuous distribution to a discontinuous distribution. The results of this research guide the subsequent production of heavy oil.