According to initial studies on cluster desiccation disorder in grape orchards, this research were done with four factors consist of: 1- potassium with three levels (0. 300 and 600 gram per tree from potassium sulfate source) and 2- magnesium with tree levels (0, 100 and 200 gram per tree from magnesium sulfate source in grape gardens of Urmia. Results show that highest chlorophyll content obtained in T3 (K1 Mg3) which was 29.4% more than control. Effect of different ratio of potassium and magnesium on TA, pH and berry diameter was not significant but control treatment showed longer berries than other treatments. Berries weight was better in T4 (K2 Mg1) and showed 30.5% increase. Clusters with highest weight were observed in T8 (K3 Mg2). T9 (K3Mg3) showed higher TSS than other treatment and in contrast with control had 67.5% increase in TSS. For cluster desiccation degree in each treatment according to potassium and magnesium ratio, T6 (K2 Mg3), T7 (K3 Mg1) and T8 since had high potassium to magnesium ratio; highest cluster desiccation was observed in these treatments. Cluster desiccation degree in decreased in second year than first year. At different ratios of potassium and magnesium, highest leaf potassium content observed in T9 which was 7% and 10% higher than control and T3, respectively. Highest leaf magnesium content observed in T3 that potassium to magnesium ratio was low and there was not significant different with control, but there was significant difference between T3 and T7 and T8 which had higher potassium to magnesium ratio. In T3 magnesium content was 21% and 16% more than T8 and T7, respectively.