More attentions have focused on the elastic properties of fresh state cement-based materials due to the emergence of additive manufacturing techniques. Without the support of the conventional formworks, the shaping of the additive manufactured concrete structure mostly depends on the rheological properties of the fresh materials. Even though the fresh state cementitious materials' rheological properties can be well characterized by using a rheometer, no previous study has investigated the effective and reliable real-time monitoring methods for in-situ rheological properties monitoring. This paper attempts to investigate the feasibility of using the piezoelectric-based electromechanical impedance (EMI) method to fill this gap. The EMI test and the rheological test were performed simultaneously. The calculated sensing index from EMI signals displays an excellent linear correlation with the results from the rheometer. The findings from this study proves that the EMI method is promising for in-situ monitoring of the fresh state cementitious materials’ rheological properties.