This paper deals with an experimental study on masonry units made of iron ore tailings in compressed earth block. Compressed earth blocks (CEB) or stabilised mud blocks (SMB) are widely accepted as energy efficient alternatives to burnt clay bricks. Natural river sand is often used to obtain optimum soil gradation in the production of SMB. In order to reduce adverse impacts of indiscriminate mining of natural sand, iron ore tailings (IOT), which is a mine waste, is used as an alternate to the natural river sand. Based on the gradation of soil used for production of SMB, optimum mix proportion of soil, sand and cement was fixed and the sand fraction was replaced by IOT at 25%, 50% and 100%. The block characteristics like wet compressive strength, water absorption, initial rate of absorption and linear elongation were examined and discussed. From the experimental results it is found that considerable amount of sand can be replaced by IOTwithout compromising desirable characteristics of SMB used for masonr