In this work, we apply close-range photogrammetry with unmanned aircraft systems to quantify erosion with millimetric spatial resolution in agricultural plots. We evaluate the proposed methodology against the traditional runoff method on active plots. A database of digital elevation models was constructed with a ground sampling distance of 7 mm/pixel and maximum root-mean-square total error of 4.8 mm, which allowed the follow-up of soil erosion dynamics within the runoff plots for a period of three months. Good agreement of the photogrammetric estimations with respect to field measurements was observed, whereas it provides a more detailed spatial information that can be used for precise soil loss dynamic studies.