Abstract: The purpose of this paper is to provide a theoretical model of tidat strain ror practical application. This model consists of two parts, i.e., body tidal strain as a consequence of the attraction by the sun and the moon and loading tidal strain caused by the action of ocean tides. For the former, in order to save computation time, we start from Wahr's tidal model, but make a few simplications, so that the components of strain tensor can be obtained from the tide-generating potential directly. As to the latter, the effects of four main ocean tides, i.e., M2, S2, O1, K1, are taken into consideration. The eotidal maps used are Schwiderski's global maps associated with the local maps of China Sea.