The total and differential leucocyte counts were estimated in 100 consecutive cases operated for acute appendicitis. Leucocytosis was seen in 52% of cases. 480/0 of patients had a leucocyte count below 10000 per c. mm. A study of the differential count was also made to see if this parameter could be used as a specific diagnostic aid. Though the neutrophil count was high in 74% of the cases, the comparative count among the below 10000 per c.mm. group was not significant. It is concluded that the total and differential counts are of limited value in the assessment of these patients. It is suggested that such estimation be used as a supportive aid only. In those doubtful cases with normal or low counts, frequent clinical reviews should be done and reliance placed on clinical assessment rather than laboratory information.