Abstract: Nitrogen uptake efficiency in wheat (Tritcum aestivum L.) as influenced by nitrogen level and weed-crop competition duration was determined at the Agronomic Research Area, University of Agriculture, Faisalabad during 1998-99. The data showed that yield, yield parameters of wheat, weed growth and nitrogen uptake by weeds increased with increased nitrogen application levels while weed population was not affected significantly. On the other hand yield and yield parameters in wheat decreased with an increase in the weed-crop competition durations while weed growth and nitrogen uptake by weeds increased by increasing the competition duration.