The application relates to a substation space three-dimensional protection device and a substation space three-dimensional protection method based on an infrared technology. The device comprises first to fourth detection columns arranged at the four corners of a substation respectively. The upper and lower ends of the first to fourth detection columns are respectively equipped with probes A, B, C, D, E, F, G, and H. An infrared alarm relay is connected at the back of each probe. The infrared alarm relays connected with the probes A, B, C, D, the infrared alarm relays connected with the probes A, B, E, H, the infrared alarm relays connected with the probes B, C, E, F, the infrared alarm relays connected with the probes C, D, F, G, and the infrared alarm relays connected with the probes A, H, G, D are connected with a first logic gate circuit, a second logic gate circuit, a third logic gate circuit, a fourth logic gate circuit and a fifth logic gate circuit respectively. After being connected in parallel with one another, the first to fifth logic gate circuits are connected with the input end of an alarm circuit. The device has a simple structure, and is easy to set up. Invasion judgment is timely and accurate, and there is no dead angle. Effective guarantee is provided for substation protection work.