An intelligent system for a bicycle is provided with a control assembly including a saddle control device, a sensor device, a digital camera, a lighting device, a warning device, and a power supply for supplying DC power to above components; and a display assembly including an LCD screen, a processing module, a communications module, and a power module for electrically interconnecting the LCD screen, the processing module, and the communications module. The saddle control device includes a microprocessor, a memory, and a wireless communications module. The sensor device includes an optical sensor, a thermometer, an acceleration sensor, a barometer, a gyroscope, an electronic compass, a radar, and a GPS. The digital camera includes a rear camera. The lighting device includes an auxiliary light, a rear light, directional lights, and decoration lights. The warning device includes a loudspeaker and a vibration module.