In order to study the effect of foliar and soil application of Zinc on grain weight and some biochemical traits of wheat (Triticum aestivum L.) under soil salinity, an experiment was conducted as factorial based on randomized complete block design with three replications in research greenhouse of University of Mohaghegh Ardabili in 2018-2019. Experimental factors were: soil salinity levels [control and salinity 30, 60, and 90 mM] and four methods of application of zinc [no zinc as control, soil application zinc as ZnSO4, foliar application nano zinc oxide and combined soil and foliar application of zinc]. The results showed that the both application ZnSo4 and foliar application nano Zn oxide under 90 mM soil salinity condition increased significantly 20.24, 17.68, 13.16, 32.88 and 14.08% of catalase and peroxidase enzymes activity, anthocyanin, proline and soluble sugars content respectively in comparison with no application of zinc under 90 mM soil salinity condition. Also, both soil application ZnSo4 and foliar application nano Zn oxide under non-salinity condition decreased hydrogen peroxide and malondialdehyde content in comparison with no application of Zinc under 90 mM soil salinity. Both soil application ZnSo4 and foliar application nano Zn oxide under non-salinity condition had the highest grain weight (1.016 g per plant) compared to the application of this treatment combination at other salinity levels. It seems that both application of ZnSo4 and nano Zn oxide can increase weight yield of wheat under salinity condition due to improving biochemical traits.