In order to investigate the effects of methyl jasmonate and potassium on resistance to chilling of pistachios seedlings, a factorial experiment was carried out in a completely randomized design with three replications in greenhouse. Treatments consisted of methyl jasmonate (0, 75 and 150 µM), potassium (0, 0.5 and 1mM of potassium sulfate source) and temperature (0, -2 and -4 °C). The results showed that, leaf electrolyte leakage increased with decreasing in temperature, but with combined application of 150µM methyl jasmonate and 1mM potassium, electrolyte leakage decreased by 48, 36 and 45% at 0, -2 and -4 °C, respectively. Also, at the temperature of -4 °C, with the combined consumption of 150µM methyl jasmonate and 1mM potassium, the concentration of proline, soluble sugars, and phenolic compounds increased by 88, 34, and 33%, respectively, compared to control plants. Also, the results of this experiment showed that with decreasing in temperature, the concentration of carotenoids, the content of soluble proteins and starch decreased, but with the combined consumption of 150µM methyl jasmonate and 1mM potassium, the value of these parameters increased by 95, 86 and 49%, respectively, compared to the control at temperature -4 °C. Based on the results obtained from this research, it was determined that in the conditions of chilling stress, the combined use of methyl jasmonate and potassium through the improvement of photosynthetic parameters and osmotic regulators can reduce the effects of frostbite on pistachio seeds.