Aiming at the structure features and construction methods for the south anchor caisson foundation of Taizhou Yangtze Highway Bridge, this paper presents a design scheme of security monitoring in construction. The result from monitoring data in construction shows that the horizontal tension stress which near blade foot at the bottom of well are greater in initial well sinking. It will effectively guide the well construction with the physical quantity as the control index of well sinking. Sidewall earth pressure increases first, and then decreases with the increase of embedment depth.