BACKGROUND: Deep brain stimulation (DBS) is a surgical technique used to alleviate symptoms in patients with advanced Parkinson's disease (PD). It is a reversible procedure and its effect is based on electrical modulation of the nervous system and has considerable advantages in morbidity-mortality when compared to lesion techniques such as thalamotomy and/or pallidotomy. The objective was to evaluate the adverse events during the surgical placement of leads in the subthalamic nucleus for the treatment of Parkinson's disease. METHODS: A retrospective data collection was made in a total of 130 patients in whom we performed 272 procedures for the implant of leads in the subthalamic nucleus between May 1998 and December 2005. All the patients were operated by the same surgeon, in the same institution and with the same surgical methodology. The complications under evaluation were: aborted procedure, misplaced leads, intracranial haemorrhage, seizures, hardware complications and other complications. RESULTS: 130 patients were treated (62 women, 68 men; average age 62 (36-74) years). The average duration of disease from the time of diagnosis to operation was 15.3 years (4-28 years) and the mean follow-up was of 37 months (3-93 months). One hundred and twenty four patients were implanted bilaterally and 6 unilaterally. 62% did not present any complications, 30% had one complication, and 8% more than one complication. Aborted procedures amounted to 5.14% of all procedures, misplaced leads 2.2%, intracranial haemorrhage 3.3%, seizures 4.7%, hardware complications 1.8% and other complications 5.1%. CONCLUSION: Deep brain stimulation surgery is an effective and safe method to treat Parkinson's disease with a low incidence of permanent adverse events.