Neurologic involvement occurs in approximately 20% of patients with primary Sjögren syndrome (SS). However, the diagnosis of SS with neurologic involvement is sometimes difficult, and central nervous system (CNS) manifestations have been described rarely. We conducted the current study to describe the clinical and laboratory features of SS patients with neurologic manifestations and to report their clinical outcome. We retrospectively studied 82 patients (65 women and 17 men) with neurologic manifestations associated with primary SS, as defined by the 2002 American-European criteria. The mean age at neurologic onset was 53 years. Neurologic involvement frequently preceded the diagnosis of SS (81% of patients). Fifty-six patients had CNS disorders, which were mostly focal or multifocal. Twenty-nine patients had spinal cord involvement (acute myelopathy [n = 12], chronic myelopathy [n = 16], or motor neuron disease [n = 1]). Thirty-three patients had brain involvement and 13 patients had optic neuropathy. The disease mimicked relapsing-remitting multiple sclerosis (MS) in 10 patients and primary progressive MS in 13 patients. We also recorded diffuse CNS symptoms: some of the patients presented seizures (n = 7), cognitive dysfunction (n = 9), and encephalopathy (n = 2). Fifty-one patients had peripheral nervous system involvement (PNS). Symmetric axonal sensorimotor polyneuropathy with a predominance of sensory symptoms or pure sensory neuropathy occurred most frequently (n = 28), followed by cranial nerve involvement affecting trigeminal, facial, or cochlear nerves (n = 16). Multiple mononeuropathy (n = 7), myositis (n = 2), and polyradiculoneuropathy (n = 1) were also observed. Thirty percent of patients (all with CNS involvement) had oligoclonal bands. Visual evoked potentials were abnormal in 61% of the patients tested. Fifty-eight patients had magnetic resonance imaging (MRI) of the brain. Of these, 70% presented white matter lesions and 40% met the radiologic criteria for MS. Thirty-nine patients had a spinal cord MRI. Abnormalities were observed only in patients with spinal cord involvement. Among the 29 patients with myelopathy, 75% had T2-weighted hyperintensities. Patients with PNS manifestations had frequent extraglandular complications of SS. Anti-Ro/SSA or anti-La/SSB antibodies were detected in 21% of patients at the diagnosis of SS and in 43% of patients during the follow-up (mean follow-up, 10 yr). Biologic abnormalities were more frequently observed in patients with PNS involvement than in those with CNS involvement (p < 0.01). Fifty-two percent of patients had severe disability, and were more likely to have CNS involvement than PNS involvement (p < 0.001). Treatment by cyclophosphamide allowed a partial recovery or stabilization in patients with myelopathy (92%) or multiple mononeuropathy (100%). The current study underlines the diversity of neurologic complications of SS. The frequency of neurologic manifestations revealing SS and of negative biologic features, especially in the event of CNS involvement, could explain why SS is frequently misdiagnosed. Screening for SS should be systematically performed in cases of acute or chronic myelopathy, axonal sensorimotor neuropathy, or cranial nerve involvement. The outcome is frequently severe, especially in patients with CNS involvement. Our study also underlines the efficacy of cyclophosphamide in myelopathy and multiple neuropathy occurring during SS.