Purpose: To assess response to HDR interstitial brachytherapy in carcinoma cervix patients who are not candidates for intra-cavitary brachytherapy post external beam radiation therapy and concurrent chemotherapy. Methods and Materials: Thirty four carcinoma cervix patients (23 patients with stage IIIB, 3 patients with stage IVA, 8 patients with post surgery vault recurrences, 32 with squamous cell histology and 2 with adenocarcinoma histology) who received definitive concurrent external beam radiation therapy and chemotherapy following which patients not suitable for intra-cavitary brachytherapy were treated with HDR interstitial brachytherapy using Martinez universal perineal implant template and analysed for response.Treatment schedules of HDR interstitial brachytherapy depending upon the residual disease after concurrent external beam radiotherapy and chemotherapy are 20GY in 5 fractions, 16.5GY in 5 fractions, 17.5GY in 5 fractions, 9GY in 1 fraction, 22.5 GY in 5 fractions and 18GY in 4 fractions. Results: Complete response was seen in 19 patients, 6 patients had partial response and 9 patients had progressive disease. Conclusion: HDR interstitial brachytherapy is a feasible option and alternative in patients who are not suitable for intra-cavitary brachytherapy following concurrent external beam radiotherapy and chemotherapy for better local control.