In order to achieve the increasing demands for the steelmaking industry in terms of efficiency and environmental sustainability, several alternative routes of ironmaking have been developed in the last decades. Some of these developments are based on the fluidized bed technology, because of the advantage to use fine iron ores directly in the process. The focus of this thesis was the investigation of the fluidization-, oxidation- and reduction behaviour of fine magnetite iron ore concentrates. The analysis of the fluidization behaviour was carried out in a fluidized bed reactor with a grid diameter of 68 mm. The process of the oxidation was tested with a rotary kiln at laboratory scale and a high pressure thermogravimetric analyser. For the investigation of the reduction behaviour, the fluidized bed reactor and the high pressure thermogravimetric analyser was used. For the reduction tests, untreated as well as oxidized magnetites were reduced with hydrogen and analysed. These tests have shown, that the reduction of the magnetite can be improved by a previous oxidation. In addition, a minimum degree of oxidation could be determined in order to achieve a similar reduction rate like a hematitic ore. The fluidization tests have shown, that a previous oxidation has a positive influence on the fluidization behaviour of fine magnetite iron ores. The untreated fine magnetite iron ores were difficult to fluidize, but with a previous oxidation step a good fluidization behaviour could be achieved. The oxidation tests were used to develop a mathematical model of the kinetics of the oxidation process. With this model it is possible to calculate the limiting step of the oxidation at given experimental conditions.