Disclosed is a method for analysing cells, in which cells are separated and the individual cells pass via a measurement region of a unit for spatially resolved radiation intensity measurement, wherein, for at least one of the separated cells, when passing via the measurement region, a time sequence of spatial intensity patterns of an electromagnetic radiation emitted from and/or influenced by the cell is created, the optical flow of a respective two of the spatial intensity patterns is calculated for at least one portion of the sequence of intensity patterns using a computer unit, and an evaluation of the calculated optical flows occurs. Also disclosed is a device for analysing cells, comprising a device for separating cells, a unit for spatially resolved radiation intensity measurement, and a computer unit for calculating the optical flow of a respective two of the created intensity patterns, and for evaluating the calculated optical flows.