This study utilized embedded piezoelectric transducers for monitoring of cement hydration process. Longitudinal ultrasonic transducer which was suitable for being embedded in cement paste was prepared by cutting PZT rods and coating epoxy layer. The transducers were used to generate and receive ultrasonic waves to continuously observe the hydration of cement paste. The characteristics of wave parameters such as wave velocity, amplitude and frequency were used to interpret the hydration process of cement. Relationship between the character values of the wave and the process of hydration could be established. Therefore, it is feasible to observe the hydration progress using this technology. The coupling problem existed in traditional ultrasonic monitoring of hydration can be solved and the whole life monitoring of cement materials can be also achieved through this method.