The efficiency of oil extraction from oil seeds is affected by seed harvesting time, drying methods, seed storage conditions and finally the means of seed transportation to the factory. To determine the grain moisture content at harvest  and its effect on seed while on drying trails, (employing different canola dryers), a study was conducted in Mazandaran province in 2009. A factorial complete randomized design of 6 replications along with a factorial complete randomized block design of 3 replications were applied for an analysis of grain quality and as well as for energy consumption respectively. Levels of moisture content consisted of 15, 20 and 25 percent (wb) and the dryer systems included: oar, LSU and steam for drying up of the seeds. The results indicated that the loss in the product following drying was found to be in the range of 0.4%-1.8% for removal of impurity. Reduction due to grain immaturity ranged from 1.3% to 2.3% and the ranges of loss due to damaged seeds and seed oil content stood at 1.9%-0.5% and 2.6%-1.2% respectively. The results revealed that the value of energy utilization, energy utilization ratio, thermal efficiency and drying capacity varied as: 682.45-171.41 KJ/s, 0.634-0.285, 14.2%-25.29% and 7.59-1.26 Ton/h respectively. Finally it was shown that a 15% grain moisture content at harvest time and the seed being dried by a steam dryer to be the most  suitable treatment for the conditions in which the experiment was conducted.