Taking the double-row steel sheet pile cofferdam in first phase reclamation project of Oufei as the project background,we introduce the construction scheme and technology for the double-row steel pile cofferdam built in coastal deep soft soil foundation.For studying the safety of double-row steel sheet pile cofferdam structure,we calculate the anti-overturning and the global stability of the cofferdam,carry out a numerical analysis of the whole construction process of cofferdam by the finite element method,and obtain the stress state of the steel sheet pile and tie rod and the deformation of the cofferdam under different construction conditions.The research shows that:the safety of cofferdam structure meets the specification requirements,the deformation of cofferdam calculation by finite element method is larger than that under the actual condition,which proves that the analysis of cofferdam structure safety by this method tends to be safety;the construction condition of the maximum internal force in the steel sheet pile and the tie rod is different between the front and rear of cofferdam.It is suggested that the whole construction process should be simulated during the cofferdam design to select the worst conditions of each structure.There are certain risks using the mean high tide level to analyze the safety of cofferdam structure,and the design high tide level is recommended.