Temperature and humidity is the important physical quantities within the measurement field. Separated temperature and humidity sensors commonly used are nonlinear output and less consistently, resulting that temperature and humidity measurement methods are relatively complex. This paper presents a multi-channel temperature and humidity monitoring system with SoC MCU. It consists of microprocessor, temperature and humidity sensors, display circuit, keyboard input module, communication interface module, voice playback module and other components. The digital sensor SHT21 collects temperature and humidity information and send into SPCE061A MCU. The system has real-time LCD display and voice broadcast function. If the temperature and humidity exceed the set range, an alarm will be given. Microcontroller transfers measurement data to the computer through USB-UART converter circuit with SPCP825A and MAX232 chips. Real-time temperature and humidity changes are dispalyed and recorded on computer. The system has a simple structure, low power consumption, cheap cost, small volume and good prospects.