Mehtods and the synthetic system of field observations of phenomena in surf zone such as waves, long period variation of sea level, currents pattern, concentration of suspended load and others have been developed. Four times field observations have been conducted using these system since 1973.
　The main conclusions obtained througth these works are as follows; 1) In surf zone, wave energies are shifted to lower frequency elements from higher frequency
ones. 2) The water surface in surf zone shows a osillation of few minutes in period and four or five minutes in time duration by about ten minutes intervals. 3) Lip currents are found in nearly some and steady alongshore intervales having the deep relationship with the variation of the sea level. 4) Near the shoreline, the sea level at just behind of a location of lip currents is higher than the level in the middle of lip currents. 5) The concentrations suspended load are deeply depended to the continuity of space and time.