The mechanism of solvation of a series of symmetrical organomercury compounds of different classes has been studied. Spin-spin coupling constants of several types, where one of the interesting nuclei is the metal nucleus, were chosen as the measured parameter. The observed solvation changes in the spin-spin coupling constants have been interpreted from the viewpoint of the two most important mechanisms of solvation-electrostatic, resulting from the solvation Stark effect, and donor-acceptor. The relationship between the solvation changes in the symmetrical organomercury compounds and the electron distribution in the metalcarbon bond, and also the sign of the spin-spin coupling constants, has been examined.