An experiment was conducted in a persian walnut (Juglans regia) orchard in the north of Iran to evaluate the effects of zinc (Zn) as zinc sulfate and/or boron (B) as boric acid in foliar spray with different concentrations and combinations. Three B and three Zn concentrations (0, 174, and 348 mgÁL -1 for B and 0, 1050, and 1750 mgÁL -1 for Zn) were applied either independently or in combination. Leaf nutrient concentrations, pollen germination, fruit set, leaf chlorophyll index, nut and kernel characteristics, vegetative growth, nut weight, and nut yield were measured to assess the effects of treatments. The results showed that all B and Zn applications and combinations had a significant effect on all traits except nut and kernel diameter, shell percent, husk thickness, and pistillate flower abscission (PFA). Pollen germination, fruit set, vegetative growth, nut weight, kernel percent, nut and kernel length, and chlorophyll index were highest when B and Zn were applied simultaneously at 174 and 1050 mgÁL -1 concentrations, respectively.We thank the University of Tehran and Iran National Science Foundation for financial supports of this research. Also, we greatly appreciate the help of Mr. M. Momeni (Manager of the Shahmirzad Kesht va Sanaat Company) for providing plant materials and Soil and Water Research Institute of Iran for laboratory facilities.