Central nervous system (CNS) tuberculosis (TB) remains a serious disease with high morbidity and mortality but is often difficult to diagnose owing to less sensitive microbiological techniques. Herein, we present a case where the main complaint was staggering gait; however, the patient was diagnosed with CNS TB associated with pulmonary TB. A woman in her 70s was admitted to our hospital with a two-month history of progressive ataxia. Cerebrospinal fluid examination showed an elevated lymphocyte count; however, cranial imaging studies did not show significant findings. However, we performed positron emission tomography-computed tomography imaging owing to suspicions of paraneoplastic syndrome, which showed substantial 18 F-fluorodeoxyglucose accumulation in the lungs. A subsequent bronchoscopy exam led to a pulmonary TB diagnosis for which the patient was treated, and the patient's symptoms fully resolved. Finally, we diagnosed ataxia due to CNS TB with pulmonary TB after excluding other causes of ataxia and because of a lymphocyte-predominant increase of cells in the spinal fluid. Thus, TB infection should be considered in cases of cerebellar ataxia of unknown etiology.