The neurotmesis of elements of the brachial plexus in perinatal lesions requires microsurgical reconstruction. In this study we present our own experiences in surgical treatment of postganglionic lesions in the fifth degree of injury in Sunderland's scale. The clinical material consisted of 14 children aged from 2.5 to 6 months treated surgically due to neurotmesis of the neural elements of the brachial plexus. In 8 cases direct neurorrhaphy and in 6 cases reconstruction with sural nerve grafts were performed. During the operations material from the proximal stumps of the brachial plexus trunks was collected for histopathological examination. The analysis of the material comprised: clinical type of injury, location of postganglionic lesion and type of surgical procedure. The results of surgical treatment were evaluated using generally accepted scales (Gilbert's, Raimondi's, Al-Qattan's and British Medical Research Council scales). Comparison of the results of treatment between the surgical methods was also performed. Better results of surgical treatment were observed after direct neurorrhaphy. In our opinion the indications for these two methods are different and both operative techniques are useful in surgical treatment of perinatal brachial plexus palsy.