The important role of immunological monitoring system of epidemiological surveillance of pertussis has been estimated. In the enzyme-linked immunosorbent assay for the detection of Ig G class antibodies to Bordetella pertussis toxin the state of population herd immunity (655 persons) against pertussis has been studied in five administrative regions in the north, east, south, west and the center of Ukraine. Representative indicator groups of people of 2, 6-7 and 18-29 years old have been examined. The concentration of immunoglobulins has been expressed in DU/ml – international DRG units. The level of immunity has been assessed as high, medium, low and one making people vulnerable and seronegative. The state of herd immunity against pertussis has been low. The level of seronegative individuals to pertussis amounted to 44.7% of the patients in the country in general, ranging from 21.2% in Chernivtsi region to 57.5% in Donetsk region. The level of the immunity to pertussis has been significantly different in different regions of Ukraine. The average concentration of pertussis immunoglobulins has been 4.7 DU/ml in the examined individuals in Donetsk region, 8.5 DU/ ml – in Kherson region, 13.9 DU/ml – in Kiev region, 17.3 DU/ml – in Sumy region, 19.2 DU/ml – in Chernivtsi region. The children of 2 years old have had the higher rates of pertussis immunity in all the areas what confirms the immunological efficacy of antipertussis vaccine. The children of 6-7 years old and adolescents have been poorly protected. They have been regarded as risk age groups, requiring some additional preventive measures. The level of immunity of the adults of reproductive age has been insufficient to protect the newborns. The obtained data should be used for targeted improvement of the specific prevention of pertussis.