This study investigated the effects of genetic damage, cell contamination and apoptosis, nanoparticle silver (nano-Ag), in vitro conditions by using fibroblast cell line rainbow trout gonad (RTG-2 cell line) as a model. Experiment was done with 9 treatments of different concentrations of silver nanoparticles (NanoCid) with average size of 10 nm, containing 0 (control group), 0.01, 0.05, 0.1, 0.5, 1, 5, 10 and 50 mg/ml. Cells exposed to the desired concentration of silver nanoparticles, and after 24 hours, were measured of toxicity with the cytotoxicity test and the effects of genetic damage tests micronucleus assay. The effect of silver nanoparticles on the growth and cell morphology also were evaluated at times 24, 48 and 72 hours after being exposed to silver nanoparticles. Results showed that silver nanoparticles have strong effects on genetic damage, cell contamination and Apoptosis on celles fish and this effects are concentration-dependent. The results of cytotoxicity test showed that the concentration of nanoparticles increases the cytotoxicity effects at concentrations of 50mg / ml so that all cells were destroyed. Also results indicated an increase in the abundance of micronucleolus in all treatments in compared with control group, So that treatment 1mg / ml with 232% (P<0.05), treated 5 mg / ml with 251% and treated 10mg / ml with 261% increase in frequency of micronucleolus showed significant differences in compared with control group. In general, it can be concluded that due to widespread production and consumption of products containing silver nanoparticles, the release of nanoparticles in the aqueous environment, is not far-fetched. Therefore, studying environmental impact of releasing nanoparticles and strategies to prevent or reduce these effects is required.