This study was carried out during 2004-2006 vegetation periods to determine the most suitable sowing dates for bread and durum wheat under Isparta ecological conditions. Bread wheat (Altay-2000 and Gun-91) and durum wheat (Kunduru-1149 and Kiziltan-91) cultivars were used as experimental materials and were sowed at 5 different time (1 October, 15 October, 1 November, 15 November and 1 December) with 15-day periods. The seeds sowed in October 1 had no germination due to insufficient moisture in soil. Therefore, the first sowing date was not evaluated, and sowing dates were used as 15 October, 1 November, 15 November and 1 December with 15-day periods. Wheat cultivars and sowing dates had significant effects on ear length, number of grains per ear, thousand grains weight, hectoliter weight, head number in a square meter and grain yield. Average of two-year data showed that sowing at 1 November had the longest ear length (9.43 cm) whereas sowing at 15 October had the highest number of grains per ear (36.87 number), thousand grains weight (40.98 g), hectoliter weight (79.04 kg), ear number in a square meter (505.32 number) and grain yield (3500.60 kg ha(-1)). Seeds sowed at 1 December had the lowest values for measured traits. Delayed sowing date significantly decreased grain yield. Among the cultivars, Altay-2000, bread wheat, was the best performing cultivars.