The aim of this study was to determine the effects of tempering time and wheat hardness on flour yield (extraction rate), protein, moisture, and ash of wheat flour. Wheat flour was prepared from very soft, soft wheat and medium-hard wheat. The extraction rate ranged from 88.5 to 93%, and represents the percentage of flour obtained in relation to the amount of ground wheat. Wheat hardness was determined by Dura Tap sieve shaker (AACC 55-30 Method). The results showed that there was a significant difference (P ≤ 0.001) between tempering duration and grain hardness in affecting extraction rate. The best extraction rate was observed after 16 hours of conditioning, with shorter and longer conditioning times showing significant extraction loss (p ≤ 0.05). The moisture contents of different conditioning durations did not show significant difference (p ≤ 0.05). However the slightly highest moisture level (14.7%) was found in 16 hours conditioning time for the very soft and medium hard flour. The L* value of the very soft flour was in the range of 40.28-72.76, whereas the medium hard flour presented L* values of 32.02-49.35. Medium hard flour containing higher whole grain wheat flour levels was darker, as evidenced by the negative L*. The luminosity results were within the expectations.