In this article the possibility to use ultrasound study with calculation of splenic mass index (SMI) to assess the immune status of children living in man-caused impact conditions is justified. A comparative analysis of the prevalence of enlarged spleen and SMI values CCM by ultrasound 1 225 children aged 3 to 17 years old, living in urban areas of the Perm region and in ecologically clean regions and in the resort area of the Republic of Abkhazia was carried out. The prevalence of personal anamnestic data was analyzed at 846 children, out of the total number. The number of sickly children in urban areas more and spleen have significantly increased in comparison with rarely ill. The SMI significantly increases the likelihood of changes of some indicators general and immunological analysis of blood.