Objective Brassica juncea, a major oilseed crop, suffers substantial yield losses due to infestation by mustard aphids (Lipaphis erysimi). Unavailability of resistance genes within the accessible gene pool underpins significance of the transgenic strategy in developing aphid resistance. In this study, we aimed for the identification of an aphid-responsive promoter fromB. juncea, based on the available genomic resources. Results A monosaccharide transporter gene,STP4inB. junceawas activated by aphids and sustained increased expression as the aphids colonized the plants. We cloned the upstream intergenic region ofSTP4and validated its stand-alone aphid-responsive promoter activity. Further, deletion analysis identified the putativecis-elements important for the aphid responsive promoter activity. Conclusion The identified STP4 promoter can potentially be used for driving high level aphid-inducible expression of transgenes in plants. Use of aphid-responsive promoter instead of constitutive promoters can potentially reduce the metabolic burden of transgene-expression on the host plant.