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To take advantage of conservation tillage systems (including direct-drilling and non-inversion tillage) in Iran, it is important to have final crop yield. In 1993-94 and 1994-95 growing seasons, effects of different tillage systems on irrigated winter wheat (Qods cultivar) yield, were evaluated in the Kabootarabad Research Station located 40 km southeast of Isfahan. In this study, conventional tillage (based on moldboard plow), non-inversion (tined-implement) tillage (based on chisel plow and a locally-made implement called khishchee) and direct-drilling (including till-plant and no-till) systems were used. Seven treatments using these systems were designed. A randomized complete block design with four replications was used. The experiments were conducted on a clay loam soil .The differences between the yields were statistically significant. The results showed that the conventional tillage and no-till systems produced the highest and lowest yields, respectively. No-till yields were significantly less than both the conventional and non-inversion treatments in both years, whereas chisel plowing and conventional yields were not significantly different. Plowing depth reduction upto 15 cm in non-inversion tillage treatments did not show any significant reduction effect on the crop yield, but tilling depth of 10 cm did reduce the yield . Adding 67.5 kg ha-’ more urea to the till-plant and no-till treatments in the 2nd year resulted in relative yield (with respect to conventional treatment) increases of 11 and 0%, respectively. Results indicated that irrigated winter wheat production under no-till management in Isfahan region may not be feasible without substantial yield reduction. A reduced tillage system that is 15-cm chisel plowing, appears to be a viable management alternative to conventional practices.