A.A Malinovsky allocated 4 most important principles of the system theory: discreteness/rigidity of system, presence of feedback, occurrence of new properties at association of elements in system, a continuity and the maximal fitness in evolution. He believed that the essential factor determining life longevity of the individual are his species-specific characteristics. A.A. Malinovsky together with coworkers has revealed the attributes most connected to increase of terms of life: a high degree of the cephalization and the big sizes of a body. He also emphasized, that with an exit on a high intellectual level people have occupied especially position at which the biological factors influencing life longevity, began to lose paramount signification, value of long life has increased. The increase of life longevity has resulted in the important consequence--to increase of the number of diseases at late age. The diseases with hereditary predisposition have got the big weight. A.A. Malinovsky considered 4 basic levels of a condition of functions of an organism. The level of the maximal pressure--mobilization of all forces of an organism on type of "emergency alarm", promotes wear process of an organism and disorder of its separate functions. Damage of the weakest link translates an organism from a stable condition in pathological when the depression of one function reduces a level of others which in turn, even more can suppress the first, resulting in to a vicious circle (a positive feedback). A.A. Malinovsky has entered concept about increasing "disregulation" of the functions of an organism during ageing as to the main reason limiting human life. He assumed, that such rigid system (organism) which has strong link (subsystem), and other subsystems function approximately at one level has the greatest stability. It is possible, that presence of weakest links is connected to size of a genetic load. Our paper demonstrates the importance of A.A. Malinovsky system approach for such field of knowledge as gerontology.