Abstract: In this paper, focusing on the suspended matter (in water), water (Pb in water) and sedimentary (Pb in sediment) phases of Pb in the Caofeidian offshore engineering marine, trend analysis and multivariate statistical correlation analysis method is proposed for analyzing the trend and correlation among the suspended matter, water and sedimentary phases of six years.The aim is to reveal the evolution law and enrichment characteristics of Pb under the influence of artificial disturbance factors.Trend analysis results show that with the increase and decrease of suspended matter, the water phase presents the basic same regularity, but the sedimentary phase is showing the opposite trend.Simple correlation analysis results show that the suspended matter was weak positive correlation with the water phase, suspended matter was a strong negative correlation with sedimentary phase, and a weak negative correlation existed between water and sedimentary phase.Compared with simple correlation, partial correlation results show that the correlation change of water and sedimentary phase is the biggest, that is to say, the water and sedimentary phase is greatly influenced by suspended matter.The correlation change of suspended matter and water phase is lower than the correlation change of water and sedimentary phase.The suspended matter and sedimentary phase is weakly influenced by water phase, owing to the small correlation change.The multi-phase change trend and correlation research of Pb has important practical significance to provide the guidance for nearshore environmental management and engineering construction.