Stable inheritance and sustained-high level expression of foreign genes in the progeny are the most critical factors for successful application of genetic engineering in agriculture. In this study, we have transformed cry1Ia5 into tobacco chloroplasts and studied the expression, inheritance and resistance offered against Helicoverpa armigera over two generations. Under rice chloroplast transcription elements, the Cry1Ia5 protein accumulated up to 3% of total soluble protein in leaf tissue which is ~ 300 fold more when compared to the expression of the same protein in the nuclear transformed plants. Transgenic plants offered complete protection against larvae of H. armigera, irrespective of development stage. Analysis of T0, T1 and T2 generation plants revealed site-specific integration, maternal inheritance and uniform expression of transgenes without imposing any yield penalty. Our results suggest that the overexpression of insecticidal toxin coding genes in chloroplasts would be an effective strategy to delay the emergence of resistance among phytophagous pests.