Abstract: To investigate the characteristics of double-convex cross-shore mudflat profiles, ten benchmarks were set on the intertidal flats in the south of Chuandong River (Yanchen, Jiangsu). The surface elevation of the intertidal flats was monthly measured from September 2012 to November, 2013. Two convex points are found close to the mean high and low tidal levels. The upper intertidal flats are less affected by tidal currents and relatively stable. The elevations of the mudflats located between the mean high and low tidal levels vary considerably during different seasons and appear to be erosive at a year-long scale. The lower intertidal flats are subjected to severe erosion and the associated seaward slope becomes steeper. From the upper to lower mudflat, the cross-shore profile shows a ‘stable—accretional—stable—accretional—erosional’ characteristic with two siltation peaks.