In 2001-2003, the authors conducted a randomized study at the "Zhemchuzhina" (Pearl) tuberculosis sanatorium (Saint Petersburg) delivering a therapeutic-and-prophylactic care to preschool children infected with Mycobacterium tuberculosis (MBT) and to patients with tuberculosis. Their parents were questioned by a specially complied questionnaire including open and close questions and the data were copied from the children's medical records. The sample amounted to 390 parents of the children aged 4 to 7 years; of them 70% were infected with MBT and 30% were ill with tuberculosis. Boys and girls accounted for 46 and 54%, respectively. Their mothers (67.7%), grandmothers (18.7%), fathers (12%), and other relatives (1.6%) filled in the questionnaire, by indicating the size of family, living and material conditions, education, and parents' occupation, nutrition pattern, family relations, a possibility of spending time on a child. Particular attention was given to the epidemiological characteristics of a family and to the level of knowledge of tuberculosis. The study has demonstrated the parents' low awareness of tuberculosis, which has been established through rumors, their repetition of stereotypes, such as their recognition of the role of a diet alone in the treatment and prevention of tuberculosis infection, with rather high assurance of their knowledge and unwillingness of enriching it. This leads to the fact that parents begin to ignore the problems associated with their child's health as to tuberculosis, thus having a negative impact on the physical and mental health of the parents themselves.