[en] The aim of this work was to evaluate and compare the Entrance Surface Dose (ESD) on children chests during x-ray examinations in a public and private paediatric hospitals of Belo Horizonte city in Brazil. Patient's data and radiographic parameters of 295 x-ray examinations of chest (AP and PA projections) carried out at two paediatric hospitals were recorded. Tube outputs were measured for different exposure conditions and doses were evaluated with the DoseCal software. Results showed a wide range of ESD values due to variations in patient size and exposure parameters. Although, in most cases, ESD values lower than values from published works in Brazil and from the Dose Reference Level of European Community, the results suggest the need of optimisation procedures, mainly concerned with exposure parameters. (Author)