Objective: To measure the fairness of PET-CT allocation in China, and to explore the influence factors of distributional fairness, and to provide policy recommendations for improving the fairness of distribution. Methods: The PET-CT allocation data of China were collected, and the fairness of PET-CT distribution was measured by the concentration index and the Theil index. Results: At present, the concentration index of PET-CT distribution among the provinces is 0.32, and the fairness of the PET-CT allocation is significantly higher than that before the implementation of the allocation planning. The concentration index of PET-CT in public hospitals is 0.318, which is slightly lower than that of all PET-CT distribution. The internal Theil index of PET-CT is 0.109, which is the main factor affecting the distributional fairness. The distribution difference of PET-CT is bigger in the eastern region than in the central and western regions. Conclusion: The allocation fairness of PET-CT has improved. The allocation planning is propitious to improve the fairness of PET-CT distribution, and the distributional differences in the eastern, central and western regions are the main factors leading to the unfairness