Some agronomical characteristics of newly improved synthetic sunflower varieties were investigated during the years 1994 and 1995 at Uludaǧ University, in the Faculty of Agriculture, Field-Crops Department. 12 inbred lines considered suitable for combination were separated into three different mixtures producing the synthetic lines Syn-O(A), Syn-O(B) and Syn-O(C), each containing 4 different inbred lines. Synthetic 1(A). Synthetic-1 (B) and Synthetic-1(C) were obtained from open pollination of these 3 mixtures of synthetic lines in the first year of research. In addition. Synthetic-1 (D) was formed by open pollination of all the inbred lines (Syn-O(D)). In the second year, four synthetic varieties, four different mixtures of inbred lines and 2 standard varieties, Vniimk8931 and Sunbred-281 (commercial hybrid), were sown in a random block pattern of four replications. According to the results of the research, the mean values of the characteristics in the synthetic varieties varied from 154.5 to 169.6 cm for plant height. 17.7 to 20.3 cm for head diameter, 856 to 1080 unit for the number of seeds/head. 54.5 to 63.4 g for the 1000-seed weight. 50.0 to 58.5 g. for seed yield/head and from 2155 to 2442 kg/ha for seed yield. In this study, it was determined that the synthetic varieties were superior to the standard varieties in terms of seed yield, seed yield per head. 1000-seed weight and head diameter.