Abstract: The study focuses on the acceptability level of interlocking blocks as masonry materials for housing construction in Nigeria. Empirical survey was conducted among selected leading professionals in the building industry namely Architects, Engineers, Quantity Surveyors and Builders through questionnaire, observations and interview methods. Two hundred questionnaires were administered randomly to these professionals in 4 out of the 6 geo-political zones in Nigeria, out of which 120 were good for analysis. Analysis of results reveals that; interlocking blocks have high acceptability index while professionals and clients showed high preference for the use of the material as an alternative for the conventional sandrete blocks.