Introduction: Diagnosis of neuroborreliosis may be difficult. Neuroborreliosis mainly results in lymphocytic meningitis and in meningoradiculitis. Case report: We report the case of a patient who developed a sudden facial diplegia, revealing neuroborreliosis proved by positive blood and cerebrospinal fluid serology. The patient had no previous history of tick bite and migrans erythema. The patient was given ceftriaxone therapy (2 g/day for 21 days), leading to resolution of all clinical symptoms. Conclusion: Our report underscores that neuroborreliosis should be considered in patients exhibiting facial diplegia. Thus, Lyme serology should be performed systematically in these patients. Altogether, early management is crucial, before the onset of neurological manifestations at late stage, leading to disabling sequelae despite antibiotic therapy