Selenium (Se) is a beneficial element for higher plants and its positive effect on plants growth and performance has been reported. Effect of Se under non-stress conditions especially during reproductive phase has not been attracted enough attention. In this work effect of Se supplementation at 0, 10 and 20 μg Se plant-1 was studied in canola (Brassica napus ‘RGS’) plants during vegetative and reproductive phase of growth under greenhouse conditions. Selenium addition resulted in a significant enhancement of dry matter production of vegetative parts as well as pod and seed dry weight. In addition, Se supplementation caused a considerable acceleration of reproductive events. In vegetative plants, higher photosynthesis rate, carbohydrates and protein content in the leaves was observed in Se treated plants compared with control. Our results suggested beneficial effect of Se on canola seed yield that may also contribute in improving nutritional value of canola for livestock and human.