This study focuses on the convolute bedding. There are a lot of convolute beddings in the Yellow River delta. They may be divided into two kinds according to their shapes and sizes: one is small in size (ca. 3-5 cm high and ca. 3-5 cm wide) and its shape is like a regular fold. The "anticline" of the convolute bedding is chevrony and tight and the "syncline" is broad and smooth. The other is relatively large in size (ca. 10-20 cm high) and complex in shape, being either upright cylindrical and upright tabular or upright curly tabular. Whether in the first case or in the second the center of the convolute bedding is commonly marked by a sand "ball" and sometimes there is one or a few sluicing holes in the center. The study reveals that the convolute bedding is genetically related to rapid deposition and wave-shaking. Wave shaking makes the loose sediment sluicing, resulting in the inversion of the density gradient, instability and diapiric deformation, thus forming convolute bedding.