Defined factor structure of the morpho-functional state and physical fitness of children 12-14 years old with a low level of physical health, with disharmonious physical development, low efficiency, insufficient levels of physical activity. The study involved 45 male and 51 female grades 7-8. Using 26 variables. Highlighted by three factors in each group. Set general factor for all groups - physical development. Contribution variables other factors differ in each of the study groups. Found that the first factor (physical development), high load (0.73 to 0.98) have the following characteristics: body weight, chest circumference at rest, during inspiration and expiration, girth size of the shoulder, arm, pelvis, waist and hips strong hand dynamometry. The guys on the first factor accounted 36.66% explanatory variance in girls - 26.24%. The second factor is identified with the physical readiness (for boys - 31.11% explanatory variance in girls - 17.41%).