The two-spotted spider mite (Tetranychus urticae Koch) causes significant economic damage in several crops, including common bean (Phaseolus vulgaris L.). This mite feeds by suction of leaf cellular contents, which can compromise plant development and reduce photosynthetic capacity. Considering limitations associated with chemical control and the search for more sustainable pest management strategies, nanomaterials have been investigated as a promising alternative. This study aimed to evaluate the effect of prior foliar applications of silicon-enriched carbon nanoparticles (C-dots-Si) on infestation of T. urticae in bean plants. The experiment was conducted at the Biotechnology Laboratory of the Universidade do Vale do Taquari – Univates, in the municipality of Lajeado, Rio Grande do Sul, Brazil. From the V2 developmental stage (15 days), bean plants received three foliar applications of C-dots-Si with an interval of 7 days between applications. Five days after the last application, two adult females of T. urticae were released on each leaflet of plants. Three treatments were evaluated: control (without C-dots-Si application), and C-dots-Si at concentrations of 0.2 and 0.4 mg mL?¹. Ten days after infestation, evaluations were performed on five plants per treatment. To quantify infestation, mobile forms of the mite and egg deposition were counted on leaves located in the apical and median regions. Basal leaves were not considered in the analyses because they were used for the initial release of females at the beginning of the experiment. At the time of collection, these leaves showed a higher degree of senescence and lower nutrient availability due to their greater physiological age. Regarding the number of mites, a significant reduction of 74% and 50% was observed in apical and median leaflets, respectively, with the use of C-dots-Si at the concentration of 0.2 mg mL?¹. At the concentration of 0.4 mg mL?¹, a significant reduction of 50% was observed only in the median leaflets. Similarly, the application of C-dots-Si at the concentration of 0.2 mg mL?¹ significantly reduced the number of eggs by 90% and 57% in apical and median leaflets, respectively. At the concentration of 0.4 mg mL?¹, significant reductions of 85% and 76% in egg deposition were observed in apical and median leaflets, respectively. Overall, the results indicate that applications of C-dots-Si can reduce T. urticae infestation in bean plants, suggesting potential use of this strategy as a complementary alternative in management of this organism.