[Objective] The present study aimed to elucidate the response of the potato root system to drought stress at different stages of plant development. Additionally, the study sought to identify the underlying mechanisms that confer drought resistance in the potato root system. The findings of this study will provide a theoretical foundation for the scientific production of potatoes under drought stress conditions. [Methods] Using Jizhang Potato No.12 as the material, an indoor potting comparative experimental design was adopted to study the changing patterns of potato growth indexes, root conformation and root physiological indexes at different reproductive periods under two treatments of severe drought [relative soil moisture content (45±5)%, CK] and normal watering [relative soil moisture content (75±5)%, XP]. [Results] The plant height, stem thickness, total root length, total surface area and total root volume of the potato were found to be significantly lower than those of the control throughout the reproductive period, as a result of the drought stress.Single plant yield, number of potatoes set per plant and starch were significantly lower in the drought stress group than in the control group, and reducing sugar was significantly higher in the drought stress group than in the control group. The roots of potatoes subjected to drought stress exhibited heightened vigor, MDA, proline, and soluble sugar levels compared to the control group, with these values increasing as the duration of drought prolonged. Additionally, the SOD and POD levels in these roots were higher than those in the control group, with SOD displaying a delayed response during the early stages and POD demonstrating a rapid surge during the tuber formation phase. [Conclusion] The growth、development and yield of potatoes were found to be impeded by drought stress. The antioxidant enzyme system and osmoregulatory substances within the potato root system exhibited a rapid response to drought stress, enabling the plant to cope with the damage caused by drought stress and demonstrating a certain degree of drought resistance.