This study shows the current scenario of sustainable livelihood security index of Allapur S Rurban cluster, located in the newly born Telengana State. Calculating economic efficiency index, ecological security index and social equity index and eventually Sustainable Livelihood Security index (SLSI) were carried out at the village levels using spatial and non-spatial data. Normalisation of the selected indicators were first done and then calculated. Results from the study indicate that the study area possesses a very low SLSI with only Narayanpur and Odandapur village which cover 11.13 per cent of the total geographical area of the cluster as sustainable and secure villages. 59.58 per cent of the geographical area and 65.83 per cent of the population are moderately sustainable category. Whereas, eight villages which accounted for 27.37 per cent population of the total cluster are under less sustainable and very less sustainable category. There is an urgent need to reorient development programmers and carry out priority-wise development investments into these vulnerable villages to provide resources and opportunities to ameliorate their ecological security, economic efficiency and social equity which further sustainable livelihood security. © 2018 National Institute of Rural Development. All rights reserved.