Soil characteristics play an important role in plant growth and yield such as saffron. In order to evaluate the effect of soil physical and chemical characteristics on morphological criteria, corm and flower yield of saffron, an experiment was conducted during year 2014. Studied soil characteristics were texture, organic carbon (OC), total nitrogen (TN), available P and K, pH and electrical conductivity (EC). Examined saffron properties were corm dry weight, flower number, flower fresh weight and stigma dry weight. Multiple regression model was used to identify the relationship between soil variables (independent variables) and saffron yield variables (dependent variables). In addition, determining the most important factors of soil physicochemical properties which have effect on saffron yield criteria was done by stepwise regression analysis. The results showed the effect of different soil textures were significant (p≤0.01) on corm yield and flower yield of saffron. The highest and the lowest saffron yield were observed in sandy loam and clay textures, respectively. The maximum and the minimum coefficients of soil chemical criteria with stigma dry weight were calculated for available K (-0.573) and pH (0.0052). Soil chemical factors affecting stigma dry weight based on stepwise regression analysis determined were available K, available P, EC and TN contents of the soil. Correlation coefficients of regression models for soil characteristics with corm dry weight, flower number, flower fresh weight and stigma dry weight of saffron were computed with 0.84, 0.87, 0.90 and 0.89, respectively. There also were a positive and significant relationship between corm yield and flower yield of saffron.