The performance of fibre reinforced cementitious composites depends on the interaction between the cementitious matrix and the fibres on the micro-scale. This interaction is affected by the material and surface properties of the fibre and the micro-scale characteristics of the cementitious matrix close to the fibre surface, creating the interfacial transition zone (ITZ). However, the discussions regarding the effect of the fibre surface on the formation of the ITZ and, as a result, the bond strength between the matrix and the fibres are limited. The present paper reports the progress of the ongoing research project, which concentrates on investigating the interface created by the steel fibres with different characteristics of the surface roughness and cementitious matrix. The results of this study can support the development of efficient fibre reinforced cementitious composites.