Abstract: Background and Objective: Salinity either saline water of irrigation or saline soil is considered a major factor in limiting plant growth. Nano fertilizers are used to reduce drastic effect of salinity. This study was performed to limit salinity drastic effect on plant productivity and to study the effect of SiO2 nano fertilizers foliar spray on growth parameter, yield, chemical composition of cucumber (Cucumis sativa) grown under agricultural drainage water. Materials and Methods: A field experiment was carried out in Kasr Rashwan village at Tameya province, Fayoum Governorate, Egypt during season (2015) to study the effect of SiO2 nano fertilizers foliar spray at a rates of (0, 15, 30, 60 and 120 mg L–1) on growth parameters, yield and chemical composition of cucumber (Cucumis sativa) under (agricultural drainage water). All data were subjected to an analysis of variance (One-way ANOVA) for a split-plot design, after testing for the homogeneity of error variances. Statistically significant differences between means were compared at p<0.05. Results: The outcome data revealed an increase in plant height (cm), number of leaves/plant, fresh and dry weights of leaves/plant (g), number of fruits/plant, mean weight of fruit, fruit length and yield kg/plant total yield t ha–1 as compared with the untreated plants under agricultural drainage water. Data also, demonstrated that application a foliar spray of SiO2 nanoparticle at rate of 60 mg L–1 gave a significant increase LSD<0.05 for most of growth parameter as compared to other treatments (15, 30 and 120 mg L–1). Conclusion: Accordingly, results indicated increase in nitrogen and phosphorus, content and uptake and decrease in Na content and uptake when adding SiO2 nano fertilizer. This study has identified that Silicon dioxide nano fertilizer can have a positive effect on the growth of plant and yield of cucumber.