Cyclic voltammetry (CV) is applied to monitor the sonoporative behavior of normal and cancer breast cells. Novel electrochemically produced microbubbles in the solution induce acoustic cavitation in the cells by ultrasonic stimulation (US). This makes sonoporation in the cells which exchanges ionic species between inner and outer parts of the membrane. Such ionic variations in culture media are detected by CV measurements. The differences in the CV patterns of the normal (MCF-10A) and cancerous (MCF-7) cells before and after US is related to the changed ion gradient between inner and outer parts of the cells. As a supporting result, cell membrane voltage in control cells, as an indicative of the membrane ion gradient, was measured by patch-clamp method which reveals the detected changes in CV diagrams. This phenomena would assist to achieve a new electrochemical method for cancer detection.