In order to determine the relationship between yield and physiological and phenological traits and to understand the direct and indirect effects of various parameters on the yield, this experiment was conducted on 13 genotypes of Buniumpersicumin three times in a randomized block design in plots of 4 m x 5 m in Mashhad. Result showed that the genotype Khajeh forest was significantly superior with regard to number of seed umblet-1, seed yield, bio yield and yield of essential oil. Analysis of variance showed a significant difference at p<0.05 for different traits as plant height, seed weight, total weight per plant, number of seeds per plant, number of umbels per plant, seed, umblet in umbel, number of branches, 1000 seed weight, biological yield, seed yield, essential oil percentage, essential oil yield and harvest index among accessions. Range heritability estimates were recorded from 0.53 – 0.96 for all the traits except for plant height with moderate heritability. High heritability was observed for a number of characters. Genetic path coefficient analysis revealed that appearance of the seed weight per plant traits and the total weight of each plant had the highest positive direct effect on yield, and essential oil percentage had the highest negative direct effect on essential oil yield. Path way analysis of some of traits could not be entered in the model in despite a significant correlation with essential oil. Genetic path coefficient analysis revealed that appearance of the seed weight per plant traits and the total weight of each plant had the highest positive direct effect on yield, and essential oil percentage had the highest negative direct effect on essential oil yield.