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Background: Drought is also one of the most widespread abiotic stresses that adversely effects the growth and development of plants. To investigate the effect of salicylic acid and drought stress on several physiological and chemical reactions in sweet pepper plants, the experiment was achieved as a factorial based on a completely randomized design in greenhouse. Drought stress levels were non-stress conditions (irrigation with field capacity), moderate stress (30% field capacity irrigation) and intense water stress (60% field capacity irrigation) and three concentrations of salicylic acid included 0 (as control), 0.5 and 1 mM were sprayed on the plant in three to four leaf stages. Results: The results showed that drought decreased fresh and dry weight of shoots and roots, leaf relative water content (RWC), fruit diameter and length, the index including chlorophyll and leaf area and increased electrical conductivity (EC), antioxidant activity, total phenolic content, ascorbate, polyphenol oxidase (PPO) and ascorbate peroxidase (APX) activity. After application of foliar salicylic acid, all of the above parameters, except the electrical conductivity content, increased. Conclusions: From the results of this experiment it is concluded that salicylic acid provides a better tolerance for drought stress in pepper plant through its influence on vegetative, biochemical and physiological characteristics.