The obstruction effect of littoral drift by an artificial headland was investigated using the contour-line-change model, taking the Kujukuri coast as an example. Numerical simulation was carried out assuming the seabed slopes of 1/50 and 1/100, while changing the length and the shape of the headland. The rate of the obstruction effect of littoral drift by a headland was quantitatively evaluated. It is given by the function of time after the construction. Only the construction of the headland is difficult to form a statically stable beach, and sand bypassing or sand recycling is required to prevent further beach erosion.