The demand for extending the life of concrete buildings has increased in recent years, and the requirements of concrete efficiency standards have also increased. Superplasticizers are used to meet these requirements. Previous studies have established that when superplasticizers are deposited in a high-temperature environment, their physical properties and flowability change. This study confirmed that the flowability with different binders and hardening performance of mortars were both affected by thermal stimulation. The results confirmed that the thermal stimulation effect improved the flowability without adversely affecting the hardening performance.