The use of traditional irrigation methods in farmlands causes irrigation water loss through runoff and deep percolation, and also causes non-uniformity of distribution of water along the field and leaching of nutrients from the root zone. But, the use of new irrigation methods such as pressurized irrigation methods, if designed and managed properly, can reduce irrigation water loss and increase the uniformity of distribution of water along the field. This study was performed in 2009 at Hamedan Agricultural and Natural Resources Research Center, Hamedan provine, to investigate the effect of sprinklers spacings on uniformity of distribution of water, infiltration and runoff. To obtain better results, the experiment was designed such that all sprinklers spacings were evaluated at the same field. The soil for the experimental field was clay loam and the sprinklers spacings of 27×27, 24×24 and 21×21 meters were evaluated for three sprinkler types of SAROO, AMBO and PROOT. The operating pressure for the sprinklers was 4 atmospheres. The results showed that for PROOT sprinkler, the highest values of coefficient of uniformity, distribution uniformity and water application efficiency are belonged to sprinkler spacings of 24×24, 24×24 and 21×21 meters, respectively. For AMBO sprinkler, the highest values of the above parameters were obtained for the sprinklers spacings of 24×24 meters. For PROOT sprinkler, the highest values of the above parameters were obtained for the sprinklers spacings of 21×21 meters. The comparison results of the above sprinklers showed that at sprinklers spacings of 21×21 meters, the highest values of coefficient of uniformity, distribution uniformity and water application efficiency are belonged to PROOT sprinkler. These values were 86.3, 79.8 and 77.7 percent, respectively. At sprinklers spacings of 24×24 meters, the highest values of coefficient of uniformity and distribution uniformity were belonged to PROOT sprinkler, but at these sprinklers spacings, the highest value of water application efficiency was belonged to the AMBO sprinkler. At sprinklers spacings of 27×27 meters, the highest values of coefficient of uniformity and distribution uniformity were belonged to PROOT sprinkler, but at these sprinklers spacings, the highest value of water application efficiency was belonged to the AMBO sprinkler. The results of runoff and infiltration studies for SAROO sprinkler showed that the reduction of sprinklers spacings from 27×27 meters to 21×21 meters, increases