Abstract: In order to study the effects of nitrogen and boron on canola yield and its components, in Ahwaz region, an experiment was conducted in 2005-2006 at Ramin Agriculture and Natural Resources University. The experimental design was a randomized completely block with three N rates (150, 200 and 250 kg ha-1) and four B rates (0, 2.5, 5 and 10 kg ha-1). All treatments replicated four times. Results showed that with increase of nitrogen rates, the number of siliques m-2, number of seeds per silique, 1000 grain weight, seed yield, oil yield and biological yield significantly increased but Harvest Index (HI) and grain oil percentage decreased. With increase of boron rates, number of seeds per silique, grain yield, oil yield and harvest index significantly increased, but no significant effect of boron rates on the number of siliques m-2, 1000 grain weight, biological yield and grain oil percentage was observed. The highest grain and oil yield (3095 and 1345 kg ha-1, respectively) were obtained with 250 and 10 kg ha-1 N and B, respectively. Although, the interaction effect of nitrogen and boron on economical yield was not significant, 200 kg N ha-1 and 10 kg B ha-1 had equal grain and oil yield (2803 and 1265 kg ha-1, respectively) to 250 kg N ha-1 and without B application (2640 and 1143 kg ha-1, seed and oil yield, respectively). This experiment showed that B application for canola can result in less use of nitrogen fertilizers. Therefore, B application in this experiment condition is very important agronomic factor.