The intemal wave is closely related to the seawater quality and the behavior of fish in coastal sea area. Therefore, the characteristics of intemal wave have been used extensively to make some attempts for creation of fishing grounds and nurseries. The intemal wave is generated by meteorological change of wind or atmospheric pressure, ocean current,tide and so on. The paper presented the generation mechanisms, theoretical analysis and program coded with BASIC for the calculation of two-layered interfacia=ong wave generated by tide. And it also explained the numerical calculation of two-layered interfacial long wave that was generated by tide in the region of continental shelf, submarine ridge and bay. The Coriolis forde caused by the rotation of the earth was neglected here.
