[en] This thesis presents the measurement of the structure function F₂ of the proton with the H1 detector at 10 GeV²< Q²<100 GeV² and 10^-4< x<10^-2. The analysis contains the data of the first year of the HERA operation. The applied integrated luminosity amounts to 22.5 nb^-1. Contrarily to earlier experiments of the deep inelastic scattering it is at H1 possible to apply also the hadronic final state for the reconstruction of the event kinematics. In this thesis ten methods for the reconstruction of the event kinematics are indicated and studied in the region Q²<1000 GeV² in detailed detector simulation on resolution, systematic effects, measurable kinematical range and sensitivity to radiation of photons from the electron. For H1 as most advantageous methods for the reconstruction of the event kinematics on the one hand the exclusive application of the electron information and on the other hand the combination of the measurement of the momentum transfer from energy and direction of the scattered electron with the measurement of the relative energy transfer y from the scattering of electron and quark have been proved. Thereby a new, for the range of small momentum transfers especially suited method, for the reconstruction of the scattering angle of the quark was indicated. A significant increasement of the structure function F₂ of the proton at small x. At large x the continuation to the results found in earlier measurements is continuous. At fixed x the structure function increases slowly in agreement with the predictions of QCD with increasing momentum transfer