Abstarct: This thesis was conducted with the aim of investigating the effects of foliar application of nanopotassium and amino acids on some tomato properties. Foliar application was carried out for 9 treatments including 100mg/l nanopotassium (NP1), 150 mg/l nanopotassium (NP2), 1000 ppm amino acid (AC1), 2000 ppm amino acid (AC2), NP1+AC1, NP2+AC1, NP1+AC2, NP2+AC2 and control sample in 4 stages for 7 days, 30 days, 45 and 60 days after sowing. Then the properties of plant height, leaf number, leaf area, dry weight of aerial organs, dry weight of roots and leaf chlorophyll were measured. Also, the exxpression changes in rbcS and rbcL genes under the influence of foliar spraying treatments were measured by qRT-PCR method. The results showed that foliar spraying treatments had significant effects on tomato height, total leaf chlorophyll, leaf area, number of leaves on day 61; root dry weight and shoot dry weight of tomato, but had no significant effects on the number of leaves on day 46. In all the above traits, the maximum and minimum of the measured trait were observed for the combined treatment NP1+AC2 and the control. The results showed that for foliar spraying with the combined treatment NP1+AC2, plant height on days 46 and 61 increased by 82.17% and 91.47%, respectively, compared to the control group. The number of leaves on day 61 increased by 29.50% for the NP1+AC2 treatment. The results of chlorophyll measurement showed that the average chlorophyll content increased by 28.26%, 48.72%, 59.82% and 57.65% on day 31 for NP1+AC1, NP1+AC2, NP2+AC1 and NP2+AC2 treatments respectively, and by 36.06%, 41.82%, 50.71% and 50.58% on day 46 compared to the control treatment. The results also showed that the maximum increase in leaf area on day 31 and 46 was 70.42% and 63.76% respectively compared to the control sample. The results showed that the increase in root dry weight in treatments NP1+AC1, NP2+AC1, NP1+AC2 and NP2+AC2 was 11.84%, 13.54%, 20.32% and 18.62% compared to the control group, respectively, and the average dry weight of aerial organs increased by 30.20%, 30.39%, 42.94% and 38.04% compared to the control group for treatments NP1+AC1, NP2+AC1, NP1+AC2 and NP2+AC2, respectively. Relative exxpression in the studied genes was not significantly affected by single foliar spray treatments, but combined foliar spray had significant effects on relative gene exxpression, so that for foliar spray treatments NP1+AC1, NP2+AC1, NP2+AC1 and NP2+AC2, relative exxpression in the rbcS gene increased by 33.72%, 39.92%, 61.78% and 61.48%, respectively, and relative exxpression in the rbcL gene increased by 12%, 27.95%, 48.88% and 38.70%, respectively, but the intensity of the increase in relative exxpression of the rbcL gene was less than that of the rbcS gene. In this study, the effect of potassium saturation or ion toxicity was also observed, and in combined treatments with AC2, a slight decrease in plant yield was observed with increasing nanopotassium concentration. Plant height, chlorophyll, root dry weight and leaf area were among the traits that decreased with increasing nanopotassium concentration in the presence of AC2. Also, for increasing potassium level in the presence of AC2, the relative exxpression of rbcS and rbcL genes did not change significantly and was almost constant. Overall, the results of this study showed that combined foliar spraying improved quantitative and genetic properties in tomato and can be used as an effective method to increase tomato yield.