A study was conducted near Dinsmore, SK in the Dark Brown Soil Zone to determine the landscape-scale variability of N2-fixation and N balance of a lentil crop. Stable 15N isotope dilution method was used to determine N2-fixation. A digital elevation model was used to establish the landform element complexes available at the site. Results showed that N2-fixation varies with geomorphological variations in the landscape. Both yield and N2-fixation were highest in the footslopes and lowest on the shoulders and upper level positions. A negative N balance was observed, with the deficit being lowest on the footslopes and highest on the upper level positions.