This data contains the experimental results investigating the effect of PCE-SP dosage on the early-age behavior of OPC-CSA-based mortar. Experimental techniques, including isothermal calorimetry, ultrasonic pulse velocity, compressive strength testing, Vicat needle, and dynamic flow table were employed to characterize the hydration process, setting time, and compressive strength development up to 28 days. Water-to-cement ratio of 0.3, cement-to-fine aggregate ratio of 1.0, and curing temperature of 25C were adopted for this research while all samples were prepared using Hobart benchtop mixer in accordance with ASTM standard.