Abstract: A smart pill box with the function of alarm and SMS alert is designed based on MCU STC89C52 chip, with trickle charge timekeeping chip providing the current date and time data. The SMS chip is TC35 chip.Real-time date and time data can display through LED. Time, date and alarm clock can be set by buttons. This system can be set four alarm clock numbers at the most each day. In the alarm open state, when set time is reached, the system will first alarm through the speaker, to remind the user to take medicine, if the user does not turn off the sound in one minute, then the system will automatically send a message to the phone of the user's guardian. This system has a good sensitivity of buttons, adding the SMS alert function so that better system's stability, reliability, practicability can be achieved.