Objective evaluations of population's health belong to the most important tasks of the public-health science. Such evaluations made in respect to children are of extra importance. One must comprehensively understand the potentialities and abilities of the methods used for the purpose. A comparative evaluation of 387 children, aged 10, was based on the findings of medical check-ups and on questionnaires of their parents. 37.7% of children, who were evaluated by their mothers as having good health, were diagnosed by doctors as having a chronic disease, i.e. the diagnosis did not entail any life limitations for such children. 40% of those children, who were referred to by their parents as sick (poor health), were classified by doctors as belonging not to category 3 (chronic pathology) but to a category of healthier children (category 2). Below 10% of children, who were describe by their parents as having poor health, were among those who were put by doctors on the list of group 3 on the basis of medical check-ups. As for those children who had an actively displayed chronic disease with a pronounced clinical course, like bronchial asthma, ulcer etc., the opinions of doctors and of their parents coincided in a majority of cases. The comparative evaluations of children' health based on questionnaires of their parents and on medical check-ups exposed a certain coincidence and specificity of such evaluations since they are based on different approaches.