Abstract: This paper analyzes the collapse of a deep excavation support structure in soft soils. Factors that might contributed to the failure of the supporting structure are evaluated. These factors include, selecting of the typical analytical section; selecting of supporting structure; analysis of most unfavorable working assumptions; reinforcement connections in the supporting structures; protecting the adjacent utilities; construction monitoring data; selection of threshold values for the alarming conditions. This paper also provides recommendations for the equality control in the construction, improvement in the supporting structure design and construction monitoring.