This study developed a multi-ion sensing system includes pH, potassium, sodium, and chloride ion sensors with a wireless home-care system. The pH sensor was based on a SnO2/ITO glass, and the potassium, sodium, and chloride ion sensors were based on the pH sensor with sensing membrane. Moreover, the wireless home-care system includes sensors module, portable module, Bluetooth module, personal computer (PC) terminal, and portable unit. According to the experimental results, the wireless system could successfully monitor and transmit the sensing signals.