Spatial and temporal expression of pathogenesis-related (PR) gene and proteins has been recognized as inducible defense response in pepper plants. Gene expression and/or protein accumulation of PR-1, β-1,3-glucanase and chitinase was predominantly found in pepper plants during the inoculations by Xanthomonas campestris pv.vesicatoria, Phytophthora capsici and Colletotrichum coccodes. PR-1 and chitinase genes were also induced in pepper plants in response to environmental stresses,such as high salinity and drought. PR-1 and chitinase gene expressions by biotic and abiotic stresses were regulated by their own promoter regions containing several stress-related cis-acting elements. Overexpression of pepper PR-1 or chitinase genes in heterogeneous transgenic plants showed enhanced disease resistance as well as environmental stress tolerances. In this review, we focused on the putative function of pepper PR-1, β-1,3-glucanase and chitinase proteins and/or genes at the biochemical, molecular and cytological aspects.