The present embodiments relate to a method for operating a particle therapy system. The particle therapy system includes a particle generation device, a beam generating device for generating a particle beam from at least one portion of the generated irradiation particles, a measuring device for automatically measuring a particle beam intensity of the particle beam, and a particle beam influencing device. The particle beam influencing device is configured to adjust the particle beam intensity as a function of the measured particle beam intensity and a predefined setpoint value for the particle beam intensity.