Development of herbicide-resistant crops has resulted in significant positive changes to agronomic practices, while repeated and intensive use of herbicides with the same mechanisms of action has caused the development of herbicide-resistant weeds. As of 2015, 35 weed species are reported to be resistant to glyphosate worldwide. A greenhouse study was conducted to identify characteristics which can be helpful in field mapping of glyphosate resistant weeds by using UAV imagery. The experiment included three species of susceptible and resistant weeds: waterhemp (Amaranthus rudis), kochia (Kochia scoparia) and common ragweed (Ambrosia artemisiifolia). Thermal images of these weeds were acquired before and soon after glyphosate application with a thermal infrared camera. The results indicate that there is significant difference between the canopy temperature of glyphosate resistant and susceptible weeds. This research is continuing to develop a methodology for identification and mapping of herbicide resistant weeds and weed species in commercial fields using UAS-based high-resolution imagery.