In a method and a device for automatic determination of perfusion by using a magnetic resonance system, multiple first MR data sets are thereby acquired from a volume element over time with a perfusion-sensitive imaging sequence, and multiple second MR data sets of the same volume element are acquired over time with a control imaging sequence, in particular a perfusion-insensitive imaging sequence. These first MR data sets and the second MR data sets are subjected to a statistical time series analysis in order to determine the perfusion in the volume element.