Abstract: This study aimed to discover the effect of four microelement fertilizers such as iron, zinc, manganese, copper on the growth, quality and yield of the saffron in the field. Foliage spray was applied to compare the effect of different fertilizers with various concentritions on the photosynthetic characteristics of leaves of crocus. The accumulation of carbohydrate in bulb and its bulb yield was also studied. The result showed that foliage spray of four microelement fertilizers, especially with zinc fertilizer, significantly improved the net photosynthetic rate of leaves and enhanced the ability of metabolic source. The content of soluble sugar, protein and starch in new-born corms, and corm yield increased significantly after application of microelement fertilizers, and the ability of metabolic pool was strengthened. However, excessive application of these microelement fertilizers would inhibit the growth of saffron, lower its yield and quality. Therefore,suitable application of four microelement fertilizers could promote the growth of saffron,and improve its quality & quantity. Moreover, spraying of 0.2% iron, 0.1% zinc, 0.12% manganese and 0.1% copper would achieve the best quality and yield of corms.