Aims: We present retrospective analysis of the set of 11 patient group with SCN1A gene (sodium voltage-gated channel alpha subunit 1) positive Dravet syndrome (DS). Patients were examined with suspected DS from 2010 to February 2017. The aim of the study was to analyse epidemiological and clinical data and to assess the efficacy of drug therapy and MRI and EEG findings. Material and methods: In the study the analysis of medical records of patients with SCN1A mutation positive DS and its statistic evaluation was used. We monitored development of disease, gender, types of epileptic seizures and their association with age of patient, findings on EEG and MRI, drug effect. We also evaluated the neurological and behavioral-mental status of patients. Results: In group of 11 patients, there were 7 women (63.6%) and 4 men (36.4%). Average age by manifestation of seizures was 6.5 months. All of the patients have mutation in SCN1A gene. The most frequent seizures were generalized tonic-clonic (81.8%). On the other hand the least occur ring seizures were myoclonic seizures-only 2 from 11 (18.2%). Average time from development of symptomatology to correct diagnosis was by 116 months. In patients born before 2010 it was only 19 months. Conclusion: DS is from prognostic point of view serious type of epilepsy. Since 2010, 52 samples of DS suspected patients were investigated. Eleven proven causal mutations represent 21% of samples. Early diagnostics of disease and correct management is crucial for further course of disease and has major impact on mental status and predicted prognosis.