ABSTRACT The objective of this study was to compute and compare DRIS norms for grafted and non-grafted red bell pepper crops grown in semi arid climate conditions. DRIS norms were computed with 84 samples of first young mature leaves collected during developed stage. The experiment had a completely randomized block design, and the values obtained for each plant and each variable were considered as independent replicates. Thirty-two DRIS norms nutrient ratios and coefficients of variation (CV) were computed from N, P, K, Ca, Mg, Fe, Cu, Zn and Mn analytical results. The ratios P/N and K/N in grafted and non-grafted pepper plants, showed low CV and therefore may play a fundamental role in crop production according with the DRIS norms calculated, since as light modification in the nutrient concentration led to a significant change in the nutritional balance. In conclusion, DRIS norms are sensitive for grafted and non-grafted plants. This work may signify an improvement in the nutritional diagnosis of grafted and non-grafted red bell pepper in semi arid climate conditions under a shaded greenhouse.