Objective To investigate the diagnosis and effectiveness of improved percutaneous kyphoplasty (PKP) for patients with thoracolumbar metastatic tumors, who could not tolerate anesthesia and open operation. Methods Between September 2009 and September 2010, 16 patients with thoracolumbar metastatic tumors underwent improved PKP. Of 16 patients, 7 were male and 9 were female with an average age of 64.5 years (range, 60-73 years). All patients had vertebralmetastasis tumor. The disease duration was 3-6 months with an average of 4 months. The visual analogue scale (VAS) score was 8.9 ± 0.8. No spinal cord compression and nerve root compression was observed. The involved vertebrae included T7 in 1 case, T8 in 1, T12 in 1, L2 in 2, L3 in 2, L4 in 3, T1, 2 in 1, T3, 4 in 1, T7, 8 in 1, T11, 12 in 1, T7-L1 in 1, and T12-L4 in 1. Nine patients had vertebral compression fracture with a vertebral compression rate below 75%. Results All patients were successfully performed PKP. There was no serious adverse reactions in cardiopulmonary and brain vascular systems and no perioperative death. The biopsy results showed that all were metastatic adenocarcinoma. All patients were followed up 9-18 months mean, 14 months). Complete pain rel ief was achieved in 14 cases and partial rel ief in 2 cases 6 months after operation according to World Health Organization criterion, with a pain-rel ief rate of 87.5%. The VAS score was 1.8 ± 0.6 at 6 months postoperatively, showing significant difference when compared with the preoperative score (P lt; 0.05). Two patients had cement leakages in 3 vertebrae with no symptoms at 6 months postoperatively. During follow-up, 12 patients died and the others survived with tumor. Conclusion For patients with thoracolumbar metastatic tumors who can not tolerate anesthesia and open operation, improved PKP has the advantages such as minimal invasion, high diagnostic rate, and early improvement of pain in the biopsy and treatment. It can improve patient’s qual ity of l ife in the combination of radiotherapy or chemotherapy.