Abstract Grape cv. Askari is one of the dominant cultivars of the city of Dena, which is affected by freezing temperatures of the winter every year. In order to study the primary bud necrosis and fruit set of the following year, the present research was carried out in one of the vineyards of Dena County in a twofactor factorial experiment based on a completely randomized block design with three replications and two vines per plot. In this experiment, salicylic acid (0, 150, 300 and 450 mg/l) and potassium sulfate (0, 1 and 2%) were used as spraying in one phase. Bud sampling was performed in three stages, and the primary bud necrosis percentage was recorded in each stage. Salicylic acid at 300 mg/l and interaction of 450 mg/l salicylic acid and 2% potassium sulfate had the highest effect on the reduction of primary bud necrosis of grape at 5% level, and the rest of the treatments did not have any significant effect on the primary bud necrosis percentage. The lowest mortality percentage of primary buds was observed in the second stage of sampling at 5% level. The results of variance analysis showed that the interaction of salicylic acid and potassium sulfate at 5% level had a significant effect on fruit diameter, and the remaining treatments showed no significant effect on the trait. Means comparison of fruit diameter showed that the interaction of salicylic acid at 150 mg/l and 2% potassium sulfate had the highest effect on the diameter of berry, and increasing the percentage of potassium sulfate increased the diameter of berry. Salicylic acid and potassium sulfate treatments had no significant effect on average length, berry weight, pH, TA, TSS and percentage of berry set

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