Ultrasound microscope is a useful tool for living organ and tissues observation as it works quickly and nondestructively without chemical staining. Previously, the cytoskeleton was successfully mapped by utilizing the cell elasticity, which corresponds to changes in acoustic impedance. In this research, we switched the focus to the intracellular dynamics to illustrate the biological phenomenon under cellular level. 0.05 μg/ml of demecolcine were applied to C1271 breast cancer cells to synchronize the cell cycle in mitotic phase. The result revealed that phenomena in the mitosis which until now is only observable through optical microscopy is achievable in ultrasound microscope. This implies that non-invasive intracellular observation of cancer cells is feasible, and this technique can improve the current anticancer drug development.