In this study, the performance of isotropic spunbonded geotextiles, which are used in vacuum consolidation, was tested both in the laboratory and in the field. Two kinds of isotropic spunbonded geotextiles were prepared. One was a matrix/binder structure using low-melting polyethylene terephthalate (PET) copolymer (co-PET) fibers for web bonding. The other consisted of sheath/core (co-PET/PET) fibers. Through the index test, it was seen that the performance of the sheath/core structure isotropic spunbonded geotextiles was better for use with vacuum consolidation than the matrix/binder structure isotropic spunbonded geotextiles. However, the drainage performance test, which simulates a construction environment, showed that the sheath/core structure isotropic spunbonded geotextiles were unstable. The matrix/binder isotropic spunbonded geotextiles showed better results for the drainage test and the field test results for the matrix/binder isotropic spunbonded geotextiles showed that they were suitable for use with vacuum consolidation.