Background The incidence of syphilis has been increasing in recent years, and neurosyphilis can present with various clinical features and magnetic resonance imaging (MRI) findings. Case presentation We report a rare case of neurosyphilis in a patient presenting with dizziness, altered mental status, and left limb weakness. MRI revealed changes in the right cingulate gyrus, adjacent frontal lobe cortex and subcortex. The diagnosis of neurosyphilis was confirmed by positive serum Red Unheated Serum Test (TRUST) and Treponema pallidum particle agglutination (TPPA) in cerebrospinal fluid (CSF). Treatment with penicillin G resulted in the disappearance of the lesion and improvement of the patient's clinical condition. Conclusions This case report highlights the importance of maintaining a high index of suspicion for neurosyphilis in patients with cingulate gyrus lesions on MRI and atypical neurological symptoms, even in the absence of typical risk factors or clinical manifestations of syphilis.