Analysis on safety monitoring data of Chengfeng Low Sluice,located on the dyke of Wuhan's Lanni Lake,during the rebuilding period is performed in this article.By deformation monitoring data,the variation characteristics and development trend of the cracking degrees of structural slots on the culvert and its uneven settlementsare emphatically analysed.Herefrom the safety state of Changfeng Low Sluice during the rebuilding period is evaluated.