The clustering of protein structures from the Protein Data Bank (PDB) was performed. The analysis of the conformation of interacting aromatic residues was carried out for 511 282 pairs in 35 493 protein structures with 50% identity. In proteins, pairs with parallel arrangement of aromatic residues make up 6.2% of all possible ones, which is twice as much as expected, pairs with perpendicular arrangement of aromatic residues make up 25%. We have demonstrated that 60° is the most favorable arrangement of aromatic residues in pairs, as in proteins, and for an exhaustive enumeration of all conformations of aromatic residues in pairs. Among all possible aromatic pairs, the His-His pair is found in proteins twice as often as the expected frequency of the pairs, and the His-Phe pair turned out to be less than expected one. A server (CARP – Contacts of Aromatic Residues in Proteins) has been created for calculating the general parameters/properties of interacting aromatic residues in globular proteins http://bioproteom.protres.ru/arom_q_prog/.