While susceptibility contrast gives details for MS lesions, two major changes – iron deposition and de-myelination had same contribution on QSM, increasing bulk magnetic susceptibility. In this work, we applied separation of positive and negative sources in clinical MS patients, and had a closer look of in-vivo MS lesions. We demonstrate variable appearances of MS lesions on separation maps as well as conventional imaging and QSM, and complex distribution and dynamic changes of positive (i.e. iron) and negative (i.e. myelin) in MS lesions, in cross-sectional and longitudinal observations.