In the present work, the parameters affecting the compressive strength and rheological properties (primarily yield strength of alkali-activated slag concrete are investigated. Water-to-cementitious materials and liquid-to-slag weight ratios as well as the sodium hydroxide solution concentration were adopted as the initial research variables to design the mixture proportions. A total of 75 mixtures were designed where 5 levels of water-to cementitious materials weight ratio (0.35, 0.38, 0.4, 0.41 and 0.43), 3 levels of sodium hydroxide solution (11.25, 15 and 18.75 Molar) and five levels of liquid-to-slag ratio (0.25, 0.35, 0.45, 0.5, 0.55) were plugged into a full factorial design of experiments. The slump or slump flow of the fresh mixtures were measured (after deciding on the more appropriate one based on the mixtures level of consistency), and the results were then translated to yield stress using the available models. The 28-day compressive strength of the mixtures were also measured and averaged on three specimens. The obtained results were then statistically analyzed using the Minitab software and it was found out that the liquid concentration, activator modulus (i.e., SiO2 to Na2O molar ratio) and liquid to slag volumetric ratios are the main three factors predicting the variations in yield stress and compressive strength. The analyses results suggest that the activator modulus has little effect of compressive strength and yield stress in the studied range. The liquid-to-slag volumetric ratio and the activator concentration repectively have inverse and direct effects on compressive strength, while increase in both of these parameters causes a drop in concrete yield strength. The developed regression models were found to have exceptionally high precisions and can be successfully used in optimizing or targeting the compressive strength and/or yield stress of concrete.