Bellow we present the results of mathematical simulation of the interaction of various sequences of proteins p53, p63, and p73 in accordance with the developed algorithms that were used for identifying the region of binding of various proteins during the formation of biological complexes p53-p53, p63-p63, and p73-p73. The approach developed in this work will make it possible to determine active regions of binding of polypeptide chains of various proteins and to choose and synthesize highly selective peptides that will be bound in the active center of a protein and will lead to its activation or inhibition and blocking of its biological functions. The developed model shows remarkable sensitivity to the amino acid sequences of proteins, which facilitates experimental studies and allows one to reduce the associated costs by reducing the number of measurements required according to the developed criteria. The first part describes the structure and function of proteins p53, p63 and p73. The second part presents numerical calculations and their analysis. The amino acid sequences of the studied proteins p53, p63 and p73 were taken in  with the numbers: P04637, Q9H3D4, O15350, respectively.