Abstarct: Cultivation of safflower, as an oil plant and compatible with the country's climatic conditions, can be effective in terms of water resource efficiency and production economy. In order to evaluate the grain performance and some physiological characteristics of safflower (Isfahan variety) in rainfed conditions, a factorial experiment was carried out in the form of a randomized complete block design with three replications in the crop year of 2022. The experimental treatments included potassium silicate at three levels of zero, 1 and 2 per thousand and calcium nitrate at three levels of zero, 1 and 2 per thousand. Each experimental plot had 5 planting rows with a length of 5 meters and the distance between the rows was 50 cm. The distance between the blocks is 3 meters, the distance between the plots is 2 meters. safflower seeds (Isfahan variety) were planted with a density of 400 thousand plants per hectare at a depth of 2-4 cm on March 10, 2022. The results showed that except for the number of pods per plant and the number of seeds per pod, the mutual effects of potassium silicate and calcium nitrate had a significant effect on the number of lateral branches, 1000 seed weight, seed yield, biological yield and harvest index. Although the highest weight of a thousand seeds was due to the lack of potassium silicate and the second level of calcium nitrate, the highest grain yield was obtained from the second level of potassium and calcium nitrate. The highest number of lateral branches and biological yield was the second level of potassium silicate and the third level of calcium nitrate. The interactions of potassium and calcium nitrate had a significant effect on the percentage of nitrogen and potassium in the leaves, except for the percentage of oil and phosphorus, as well as flavonoids in the leaves, as well as photosynthetic chlorophyll a, b, anthocyanine and caricocomic pigments in the leaves. The highest percentage of nitron and cariconoids in the leaves was also chlorophyll a at the third level of potassium and calcium nitrate, but in the potassium grain, the highest was the third level of potassium silicate and the second level of calcium nitrate, with the second level of potassium silicate and the third level of nitrate nitrate. The highest amount of chlorophyll b was obtained in the leaves. The highest anthocyanin of the leaves was related to the third level of potassium silicate and the second level of calcium nitrate. In general, the results can be stated that the solution of potassium silicate and calcium nitrate can have a positive effect on seed yield and physiological indicators of safflower.