Purpose To capture the evidence of inflammation dissipation and iron accumulation in MS lesions by observing lesions magnetic susceptibility change in value and range at various stages from quantitative susceptibility map(QSM).Methods Patients were selected from a clinical MS MRI database which included pre-and post-gadolinium T1-weighted images and T2-weighted image.Gd-enhancing lesions were found in baseline MRI and they were assumed to be age zero.The first follow-up MRI which included a QSM image was found to identify the lesions age.Lesions age were classified into different age groups(0,0–6 months,6–12 months and 12–24 months).The magnetic susceptibility and the volume of lesions were measured on QSM.Lesions volumes were also measured on T2w image which were co-registered with QSM images.The volume ratio of(Volume QSM – Volume T2w)/Volume T2w was calculated to compare lesions volume between QSM and T2w.Results 133 enhancing lesions were found at baseline MRI in 60 MS patients.32 lesions in 15 patients only had the baseline MRI with QSM so they were age 0.101 lesions were found at follow-up MRI in 45 patients.In the 101 follow-up lesions,39 lesions from 14 patients were age smaller than 6 months(4.08 ± 1.76 months),34 lesions from 16 patients with age ranged from 6 to 12 months(8.89 ± 1.65 months)and 28 lesions from 15 patients were aged 12 to 24 months(17.94 ± 3.65 months).The lesions susceptibilities increased with the lesion age.They were 4.21 ± 5.20 ppb at age 0 month,13.59 ± 5.28 ppb at 0–6 months,23.13 ± 9.55 at 6–12 months and 29.873 ± 8.26 ppb at 12–24 months.The volume ratio also increased with time.They were-0.90 ± 0.20,-0.31 ± 0.18,-0.05 ± 0.21 and 0.24 ± 0.39 at the age 0,0–6 months,6–12 months and 12–24 months respectively.Conclusion The MS lesion susceptibility increase with time and the volume changes between lesions on T2w and QSM show the dynamic change of inflammation and iron accumulation of MS lesions.