This study focused on the effect of trapped water on the bearing capacity of PVC pipe pile foundations. This research is divided into two models. The first model (pressure cap pipe pole) and the second model (open press pipe pole) each consist of four variations of PVC pipe diameters of 5.08 cm, 6.35 cm, 7.62 cm, and 10.16 cm (standard size PVC pipe diameter) with the same length of 30 cm. In the first type, all pipes are tightly closed at their upper ends. In the second type, all upper-end caps are given two holes, each with a diameter of 0.5 cm. Each pipe pile is alternately piled into soft soil with a moisture content of 98.8% is in a glass box measuring 120 cm x 20 cm x 60 cm. The test results of the load against decrease were analyzed using the Mazurkiwicks interpretation method. The bearing capacity of the end of the pole