Reclamation is carried out in the coastal area of Wenzhou through dredging sludge from the bottom of waterway in the sea, and large -area sludge ground is formed and then consolidated by vacuum preloading. The dredge fill ground which has been treated is urgent to be used for engineering construction. But its bearing capacity can’t meet the requirement of construction. In order to study the way of improving the bearing capacity, five test areas are designed for field tests. Modified vacuum preloading method without sand cushion is studied in different programs. According to the tests results, modified vacuum preloading method can achieve good results in the reinforcement of dredged fill soft ground. Consolidation effect can be better improved in the condition that horizontal drain pipes are encrypted or braced by PVC pipes inside. Modified vacuum preloading combined with surcharge preloading can protect the vacuum membrane and speed up the consolidation of the soft ground to an extent.