This Diploma Thesis aims to investigate the impact of mobile phone use to the driver behaviour and safety. In order to achieve this objective an experimental process on a driving simulator was carried out, in which all the participants drove in different driving scenarios. Lognormal regression methods were used to investigate the influence of mobile phone use as well as various other parameters on the mean speed. Binary logistic methods were used to investigate the influence of mobile phone use as well as various other parameters in the probability of an accident. From the models application it appears that mobile phone use leads to statistically significant decrease of the mean speed in urban and interurban environment and simultaneously leads to an increase of accident’s probability, probably due to distraction of driver attention and as a result, delayed reaction time at the moment of the incident. It appeared that in rainy conditions drivers did not present different driving behaviour, however, they had a high probability of being involved in an accident.