Aim of study was to determine combined effect of water/cement ratio, steel fibre tensile strength and volume fraction of fibre on mechanical behaviour of steel fibre reinforced concrete (SFRC), and to find optimum solutions for design parameters while fracture energy of concrete is maximised. Experimental design was done by using Response Surface Method (RSM), which is a promising approach for optimising SFRCs to meet several performance criteria such as maximum fracture energy. It was observed that matrix strength or water/cement ratio directly influenced performance of steel fibres. Both matrix and fibre tensile strengths must be taken into account as criteria.