This work investigates the effects of both soluble and insoluble chemical activators and quality improvers on hydraulic activity of ground granulated blast-furnace slag-blended Portland cement. An optimum mix consisting of 48% Portland cement, 43% slag and 9% insoluble chemical activator was firstly opted based on 28-, 60- and 120-day compressive strengths. In the next stage, different soluble non-chlorine chemical activators of the type mild alkaline and two different quality improvers including triisopropanolamine and triethanolamine (TEA) were added to the optimum mix to enhance its hydraulic activity. The experimental results showed that the addition of 0.04% TEA resulted in about 8% increase in both 28- and 60-day compressive strengths. Non-chlorine soluble chemical activators, however, when used individually or in combination with quality improvers did not result in higher compressive strengths. Complementary studies by scanning electron microscopy and X-ray diffractometry on 60-day cured hardened paste of the material showed that the microstructure is composed of an amorphous matrix in which non- or partially reacted slag particles are embedded.