Introduction. Resection of tumours of the spinal canal performing laminectomy may lead to deformities in the sagittal plane. These deformities require surgical treatment in order to restore the normal sagittal profile. Aim of paper. This paper presents patients with a kyphotic spine deformity resulting from a laminectomy performed for tumour resection and the results of surgical treatment aiming to restore the normal sagittal balance. Authors basing on the literature and own observations identify the risk factors of deformity development. Material. Material consists of 5 patients, 3 women and 2 men, who underwent a resection of tumours of the spinal canal via laminectomy and who developer pathological kyphosis that required surgical treatment. Methods. We evaluated: age at initial surgery, type of resected pathology, extent of laminectomy, need of radiotherapy, onset and progression of deformity, sagittal balance, and concomitant spinal deformities type of surgery restoring normal spine profile. Results. The inital surgery in cases was performed under the age of 10 years. One female patient apart a kyphotic deformity of the cervico-thoracic junction had also scoliosis. In 3 cases the resected tumour was astrocytoma, in one osteoblastoma and in one a subdural cyst. The extent of laminectomy ranged from 2 to 5 levels. The location of laminectomy was cervico-thoracic junction in 2 patients, thoraco-lumbar junction in 1 patient and thoracic region in two patients. Radiotherapy was applied in 4 cases. The progression of the deformity was observed during growth spurt and ranged from 72° to 155°. Surgery for kyphosis correction was performer between the age 12 to 25 years. The final kyphosis angle ranged from 20° to 86°. No intraoperative complications were noted. In one case a loss of fixation in the lower end of the fusion was observed, a reoperation was required. The follow-up period after kyphosis correction ranged from 1 to 9 years. Conclusion. Laminectomy may lead to a pathologic kyphosis; the magnitude depends on several factors like age at surgery or extent of laminectomy. It is essential to control patients with risk factors and in cases of development of kyphosis surgical means are successful in achieving good sagittal balance.