Percutaneous vertebroplasty is a popular and minimally invasive procedure with injection of polymethyl methacrylate(PMMA) into a collapsed vertebral body under fluoroscopic guidance. Several complications have been reported including leakage into the spinal canal, intravascular leakage, pulmonary embolism, subcutaneous hematoma and infection. But most of these compli- cations are happened in the early period after operation. We report a rare case of delayed spinal cord compression after vertebroplsty with polymethyl methacrylate cement and it's treatment. A 55-year-old female presented with progressive low back pain and radiating pain on both legs for 1 month and suddenly developed paraparesis for 1 day. She was already performed percutaneous vertebroplasty 6 months ago due to osteoporotic compression fracture at the first lumbar vertebra(L1). During 5 months after vertebropalsty she didn't have any neurologic deterioration or pain, but on the serial radiologic examinations after vertebroplasty, progressive compression fracture of the previously operated site was seen. Magnetic resonance imaging showed a dislodgement of solid PMMA mass compressing spinal cord severely. So she was performed the operation, that is total laminectomy L1 and pedicle screw fixation T11-T12-L2-L3 and posterolateral fusion. After the surgery, her symptoms were improved and neurologic deficit was recovered.