OBJECTIVES Multiple Sclerosis (MS) is a chronic and  progressive which represents a catastrophic  payment to patient, society and health care system . Iran, differing to the other countries in Middle- east, is considered to have a medium to high prevalence of MS. Although much is known about the MS cost in the world, there is a very paucity of the MS cost study in Iran. The aim of study was to estimate the costs and QOL  in MS individuals and determine whether these costs increase as disability progress. METHODS We studied 160  MS patients who attended  in the MS association of  Khorasan privence(the widest province in Iran  ). Quality of life was measured with MSQOL-54 instrument. Data was collected by employing a 32- item self-administered questionnaire in a face to face interview.  Parametric, nonparametric tests and descriptive statistics analysis were applied (p value<0.05). Patients were grouped into three disability stages according to their Expanded Disability Scale Score (EDSS). RESULTS The Patients mean age was 31.78(SD: 9.67  )years,% 73.8  were female and %26.3 were male , and their mean EDSS was 2.4(SD; 1.26) whereas EDSS increases , the costs also increases, which is a positive correlation. The mean QOL was 0.54 that as QOL  increases, the costs decreases, which is a negative correlation. The MS medications (Interferon )  have  a cost around $ 46625  per year for each  patient that  are subsidized about $ 24452 IR by governmental sector .Up to $ 17104  are  paid   by insurance and $ 5263 directly by patients. The costs per patient-year were calculated as $ 11560)-  27970.5591 (EDSS= 1-2.5),$ 29916.909-  30015.645 (EDSS=3-4.5) and $34678.776- 34793.22 (EDSS= 5- 7.5). CONCLUSIONS We conclude that the costs are relevant in MS ,especially when disability increases. The catastrophic cost has a high burden to patients  , society and health care system