To investigate interrelationship of some morpho-physiological traits and oil yield of Dracocephalum moldavica L. an experiment was conducted in the form of split factorial based on randomized complete block design with four replications in a greenhouse and field conditions. Results indicated a significant and high correlation of flowering shoots yield and oil percentage with oil yield under given conditions. The most direct effect in these conditions was related flowering shoots yield and oil percentage which was also evident in stepwise regression. Traits including plant height, number of sub-branches, proline and soluble carbohydrates also directly or indirectly affected on flowering shoots yield and oil percentage. In factor analysis, two factors of morphological traits and yield in greenhouse conditions and three factors of morphological, yield, and oil yield in farm conditions confirmed 92.85 and 93.06 % of total variance, respectively. Generally, reinforcing the first factor which justified the most variances among the data especially total chlorophyll, number of flowers and sub-branches, and leaf area can accelerate the flowering shoots yield, oil percentage and finally improve oil yield. Despite reduction in the oil percentage due to an increase in the amount of proline and soluble carbohydrates, these two traits through improving morphological traits in low humidity conditions can be useful in accelerating flowering shoots yield and finally oil yield. Thus, regarding flowering shoots yield (it also includes oil percentage), it is suggested to improve D. moldavica oil yield.