Postural defect is a set of postural abnormalities defined as minor single deviations from correct posture, which may be repaired with the use of appropriate exercises, passive or active. Studies concerning the evaluation of children and teenagers’ health condition have shown that the incidence of postural defects in the population ranges from 30 to 60%. The greatest threat for the development of incorrect body posture is present in the period of fast growth, namely between the age of 5 and 7 and in the period of adolescence. The most common postural defects in the population of children in Poland include: scoliosis, juvenile kyphosis of the spine (Scheuermann’s disease) and static deformations of lower extremities. Owing to the common nature of the issue and the possibility to apply effective preventive measures, it is necessary to early detect postural defects through appropriate examinations. Preventive healthcare for children is aimed at early diagnosis of irregularities in a child’s development. Screening tests among children detect three types of the motor system disorders: scoliosis, excessive thoracic kyphosis and static deformations of lower extremities and asymmetry in the length of lower extremities. Early detection of the defect prevents against its further development or the development of further abnormalities. The results of a report Health Behaviour in School-aged Children concerning the health of children clearly show that recently, there has been a substantive increase in the number of factors causing the creation of postural defects. School period is the most optimum one to carry out preventive actions in this respect. Postural defects develop in some children, despite preventive measures carried out. In accordance with the recommendations of experts, it is then necessary to perform secondary prophylaxis, which prevents further development of the defect, the creation of muscular contracture and is aimed at the so-called postural re-education. The selection of physical activity should be adequate to the type of postural defect.