SummaryMultiple sclerosis (MS) is a chronic, inflammatory, demyelinating disease of the central nervous system (CNS). Disease is often characterized by attacks and remissions. The lesions present various symptoms according to their locations in the CNS. The treatment can be divided into three categories as attack treatment, prophylactic therapy and symptomatic treatment. Glucocorticoids (GC) are used in acute attacks of MS usually in intravenous pulse form for 3-10 days several times in a year and they accelerate the remission of attacks. GC has various positive and negative effects on the musculoskeletal system. Avascular necrosis (osteonecrosis) is a common complication of GC using. GC-induced avascular necrosis is frequently seen in femoral head. GC-induced femoral head avascular necrosis (FHAVN) may occur in patients with MS. FHAVN may be asymptomatic and painless or may cause pain and limitations in the hips. Since hip pain and limitations can be seen in MS patients due to spasticity, FHAVN should be absolutely considered and ruled out in differential diagnosis. In this article, a FHAVN case developed due to high-dose GC using for several times a year in a patient while being followed-up for MS was presented, and the association of these two diseases was discussed in the light of current literature. The aim of this case report is to point out the importance of ruling FHAVN by magnetic resonance imaging (MRI) in MS patients even they have normal direct radiography findings.