Investigating the stress concentration in reinforced concrete connections under the blast loads is the purpose of the present paper. This goal was achieved by the design and analysis of the connections. The finite element package ABAQUS was used in this study to model and analyse the connections. A reinforced concrete connection which was tested experimentally was modelled and analysed in order to verify modelling. The results of modelling and experimental test were compared which demonstrated the accuracy of modelling. Afterwards, two reinforced concrete buildings with five and nine storeys were designed employing the ETABS software. A beam-column connection of the ground floor of each building was designed. The sizes of the cross-sections of the beams and columns and the spaces of their stirrups were considered differently. These connections were also modelled and analysed. The distances of the connections from the blast centre were considered as 2.5 m, 5 m, and 10 m and the blast powers were adopted as 500 kg, 1000 kg, and 2000 kg TNT equivalent mass of explosive for the analyses of the connections. The stresses created in the reinforcements of the connections owing to the blast loads were examined. It was demonstrated that as the connection was located farther from the blast centre, the stresses in the connection reinforcements were reduced. Also, the stresses in the connection reinforcements were increased by enhancing the blast power. Meanwhile, using larger cross-sections for the beam and column in the connection of nine-storey building than the connection of five-storey building transferred the stress concentration in the reinforcements to the beam and near the beam-column connection. By decreasing the stirrups spaces of the beam in the connection of five-storey building, the high stresses in the reinforcements were mainly transferred to the beam of the connection which could reduce the likelihood of the progressive collapse of the structure.