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Primary tillage operation often creates cloddy and un-even soil surface due to limited time and inappropriate moisture content in the most parts of Iran. Farmers therefore use disk harrows several times to overcome this problem, which affect soil properties, time and costs of operation significantly. The aim of this research was to develop a new combined machine for sufficient clod breaking as well as surface uniformity in one pass and the shortest possible time. The machine was combination of a disk harrow and a Cambridge roller. The combined machine was field tested in a research station with loamy soil texture. Treatments of disk harrow once; disk harrow twice and combined machine applied after moldboard plowing. The parameters of bulk density, clod mean weight diameter (MWD), penetration resistance and soil surface profile were determined and analyzed among the treatments. The results indicated that combined machine improved some soil physical properties, which were important for secondary tillage such as clod breaking and surface uniformity. No significant difference was noted between combined machine and disking twice in the most parameters. It can be therefore concluded that new combined machine would be substitute for several disking and allows operation to complete in one pass.