This research was carried out to determine the yield and yield characteristics of some sweet fennel (Foeniculum vulgare Mill. var. dulce) populations obtained from different regions in Yozgat ecological conditions. The experiment was established in Yozgat Bozok University, Faculty of Agriculture, Research and Application Area in the vegetation period of 2019, according to the random blocks trial pattern with 3 replications. In the study, the emergence of four different sweet fennel populations, biological yield (kg/da), plant height (cm), number of branches per plant (pieces/plant), number of umbellets per plant (pieces/plant), number of small umbellets per plant (pieces/plant), number of seed per plant (pieces) /plant), seed yield per plant (g/plant), seed yield (kg/da), 1000 seed weight (g), essential oil content (%), essential oil yield (L/da) were investigated. According to the results, the plant height of sweet fennel is 48.33-59.56 cm, the number of branches in the plant is 5.00-5.96, seed yield is 8.52-13.60 g per plant; one thousand seed weight is 3.82-7.435 g biological yield 708.70-1972.00 kg/da seed yield, 67.96-198.43 kg/da essential oil ratio 3- 4.20% essential oil yield 5.35-15.06 L/da was observed. Consequently, it has been concluded that the population of Tokat was found to have outstanding characteristics in terms of seed yield and essential oil yield.