The influence of Ridomil plus 50% WP, Vydate 24% SL alone or in binary mixture on some chemical constituents were evaluated in tomato leaves at different intervals of application under the field conditions. The application of tomato seedlings with Vydate led to the highest significant decrease in chlorophyll (a, b & total) and carotene contents followed by the mixture treatment and the Ridomil plus alone in the case of chlorophyll (a) and total chlorophyll only. The recommended concentration of Ridomil plus resulted in higher chlorophyll (a) and carotene contents at different intervals of application comparing to the control treatment. On the contrary, Ridomil plus had a greater significant reducing in the total soluble sugar after 1, 7 and 14 days of application, while Vydate gave significant increase in the total soluble sugar after 1 and 7 days of application. The use of Ridomil plus, Vydate and their mixture caused a significant decrease in the total soluble protein after 14 days of application. However, the minimum decrease in the total soluble protein content was found in the treatment of Vydate. Generally, all treatments caused an increase in the total free amino acids until the first day of spraying, and then a decrease occurred until the end of experiment. The nematicide, Vydate had no influence on the phenolic compounds of tomato leaves. On the contrary, Ridomil plus increased phenolic compounds in tomato leaves from 75.90, 77.45 and 78.51 in control plants to 88.74, 96.08 and 91.11 mg/g dry weight after 1, 7 and 14 days, respectively of application. Ridomil plus, Vydate and their mixture had a significant decrease in peroxidase activity of tomato leaves. Peroxidase enzyme can not restored its activity in treated tomato leaves with all treatments after 14 days of application.