Multiple sclerosis significantly affects how patients maintain the resources they consider important. The aim of this paper is to describe the moderation effect of time since diagnosis on the evaluation of resources by patients with multiple sclerosis, on the basis of S.E. Hobfoll’s Conservation of Resources (COR) theory. The study was conducted using paper and pencil methods and involved 77 patients, of whom 32 received their diagnosis less than four years ago, and 45 more than four years ago. The patients’ resource evaluation was investigated using the Polish adaptation of the COR questionnaire. Patients who received their diagnosis more than four years ago were more likely to consider vital and spiritual resources to be more important. In patients diagnosed less than four years ago, the loss of economic, political, and vital resources was significant. It is shown moderation effect of time since diagnosis. The results may for the basis for further research.