The aim of this research was to determine the effect of different drying times on the yield and essential oil content of hyssop (Hyssopus officinalis L.). The harvested fresh plant samples were dried at 35°C in the drying oven at different times (fresh herb, 24, 48 and 72 hours). Then, the essential oil content of the plant samples were determined by water distillation using the Clevenger type apparatus. In the experiment carried out, the mean values of herb yield (kg da -1 ), leaf + flowers yield (kg da -1 ), essential oil ratio (%), essential oil yield were determined as 1209.81 kg da -1 , 487.06 kg da -1 , 0.50% and 2.17 L da -1 , respectively. Results showed that different drying times were effective on yield and essential oil content of hyssop.