Abstract: To improve the marine ecological environment in Anhai Bay,we combined the actions of dredging,sedi-ments backfilling,mangrove planting and artificial islandsconstructingto restore the ecological functions.Five dred-ging plans were designed to calculated respectively the volumes of dredging materials,the volume and the rate ofsands extracted,storage capacity and tidal flux after the dredging.The results showed that the total dredging volume,sands extraction volume and storage capacity increased with the dredging depth.The increment tidal flux ofthe bay was depended on the lowest tides by average and it stopped increasing when the dredging depth exceeded1.45m.By sediments backilling,the costs for restoration and sea resource utilization could be reduced with re-sults of dumping reduction.The assessment would be an example for other bay ecological environment restorationproject.