We have evaluated the haematological values of 50 adult patients with untreated pulmonary tuberculosis (PTB) and compared them with those of 50 normal age and sex-matched controls. Anaemia (usually mild) and an invariably (but moderately) elevated ESR were observed as expected. Thrombocytopaenia and thrombocytosis were observed in equal number of patients (18% respectively). We observed significant lymphopaenia (rather than lymphocytosis) in these untreated PTB patients, occurring in 46% (p < 0.0001). Lymphocytosis was observed in only 6% of the PTB patients. Another interesting observation was neutrophilic leucocytosis, which occurred in 40% of the patients. We would suggest that in evaluating results of haematological values in suspected cases of PTB, lymphopaenia rather than lymphocytosis, should be considered.