The primary aim of the present study is to evaluate the properties of the controlled low-strength material (CLSM), which is produced using a ternary mixture of red mud (RM), slag, and a small amount of cement. The CLSM samples are prepared with various weight ratios of RM-to-slag (95/0, 85/10, 75/20, and 65/30) and a constant content of 5% cement. Properties of the CLSM are checked at both fresh and hardened stages, including flow ability, setting time, and compressive strength. Additionally, microstructural properties of the CLSM are examined using a scanning electron microscope. Test results show that properties of the CLSM mixtures are acceptable for the job site application. Analysis of the optimal mixture is further conducted based on the test results. Thus, the CLSM sample incorporating 75% RM, 20% slag, and 5% cement exhibits good physical-microstructural characteristics that conform well to the standard requirements.