To make the quality control of the leukocyte numbering in some laboratories of the former city of Tshela, was the overall objective of this research. Blood samples for leucocyte (white blood cell) counting were taken from patients at Pandji General Reference Hospital, Mimvanza Reference Health Center and Kilayika Hospital Center and the latter were examined at the laboratory of the Higher Institute of Medical Techniques of Tshela (ISTM /Tshela) with respect for standards, enacted on the subject by the WHO. Indeed, the quality control results of the numbering of white blood cells showed that the quality control parameters were good except for the parameter expression of the results with bad score at C.S.R/Mimvanza and C.H. Kilayika as well as the task parameter of Laboratory Technician with an average index at the Pandji General Reference Hospital in Tshela. In addition, the distribution of data according to age group revealed that the age group from 1 to 16 years was the most encountered with 36 cases out of 90, or 40%, on the other hand, that from 16 to 30 years was the less observed with 14 cases out of 90 or 16%. This predominance of the age group of 1 to 15 years could be justified insofar as this category contains a vulnerable group, that of children from 0 to 5 years old. It was found that according to the presentation of the data of the number of white blood cells in the laboratories, that in the sense of the HGR/Pandji, which has a high frequency of normal results with 16 out of 42 normal cases, i.e. 38 %. According to the overall quality control results of the white blood cell count, quality of the white blood cell count, the normal results were superior compared to the abnormal, with 64 cases out of a total of 90, or 71% From the comparison of the quality control and lab results, we noticed a considerable discrepancy between the lab results and its results from our study. After our analyzes we found that quality control of the WBC count was non-existent in medical laboratories, which is the cause of results that sometimes deviate from reality or standards. Our hypothesis according to which there would be the absence of quality control in the leukocyte numbering which would be the basis of the errors recorded in the expression of the results was fully confirmed.