An exhaust gas turbocharger for an internal-combustion engine has a turbine housing and compressor housing in which a turbine wheel and a compressor impeller are connected with one another shaft. The turbine housing has a spirally-extending inlet duct for the exhaust gases. Devices for the flow deflection can be provided in the inlet duct. As a result, the thermal stress as well as the efficiency of an exhaust gas turbocharger with a spirally extending inlet duct for the exhaust gases are improved.