Disclosed are an intraoral sensor and an X-ray imaging system. The intraoral sensor includes a sensor panel, a circuit unit, a memory, a battery, a casing, a first connector, and a power terminal. The X-ray imaging system includes a docking station with the intraoral sensor docked thereto, the docking station configured to provide a second connector connected to the first connector to perform at least one function of receiving the image signal stored in the memory, and charging the battery, or includes a transmission cable detachably connected to the intraoral sensor, and configured to provide a third connector connected to the first connector to transmit the image signal.