With the rapid development of indium tin oxide (ITO) in the electronic display industry, choosing which raw powders to prepare high-quality ITO targets has always been a controversial topic. In the work, in order to clearly understand the effect of the raw powders on the microstructure and properties of ITO targets and thin films, tin-doped indium oxide (dITO) and In2O3-SnO2 mixed (mITO) powders were chosen to prepare ITO targets for depositing the films and a comparative study on their microstructure and properties was conducted. It is found that, (1) dITO targets possess a higher solid solubility of tin in indium oxide and more uniform elemental distribution, while there are a higher density, a finer grain size and a higher mass ratio of In2O3 to SnO2 for the mITO targets; (2) dITO films with more coarser columnar grains and a rougher surface prefer to grow along the [100] direction in an Ar atmosphere; (3) the conductive property of ITO films only depends on the doping amount of tin and is independent of the raw powders and the preparation process of the target source; (4) dITO films possess the superior optical property and narrower optical band gap; (5) the etching property of mITO films is superior to that of dITO films due to the lower solid solubility of tin in indium oxide.