Background: multiple sclerosis (MS) is an inflammatory disorder of the brain, spinal cord, and optic nerves. MS affects more than two million people worldwide; sleep disorders are very common in the general population; their high prevalence rate suggests that MS patients will certainly be suffering from comorbid sleep disorders. Objective: study the prevalence of sleep disorders among MS patients by clinical and Polysomnography (PSG) studies. Patients and Methods: twenty-five MS patients and 12 healthy controls were examined by expanded disability status scale (EDSS) for functional disability, Pittsburg sleep quality index (PSQI) for sleep quality, Epworth sleepiness scale (ESS) for excessive daytime sleepiness, international restless leg syndrome scale (IRLSS) for restless led syndrome (RLS). PSG studies were done for all subjects for assessment of quality of sleep and sleep parameters. Magnetic Resonance Imaging (MRI) Brain was done for MS patients g to subtype it according to McDonald criteria 2010. Results: seventy six percent of MS patients had poor sleep quality according to PSQI (8.6 ±3.7). While 44% had excessive daytime sleepiness according to ESS (12.2±3.6) and 40% had RLS according to IRLSS. Patients with progressive MS (PMS) either primary (PPMS) or secondary (SPMS) subtypes had poorer sleep quality index and excessive daytime sleepiness compared to relapsing remitting MS (RRMS) subtype. PSG study showed decreased total sleep time (TST) and sleep efficiency index in MS patients with prolonged sleep latency and decreased rapid eye movement (REM) latency and higher total arousal index and periodic limb movement (PLM) index than control. EDSS of MS patients had positive correlation with PSQI and ESS. Also EDSS had inverse correlation with TST and sleep efficiency index on PSG. Conclusion: sleep disorders are prevalent among MS patients. PPMS and SPMS patients showed more prevalence of sleep disorder than RRMS with poorer sleep parameters on PSG.