The invention relates to the field of an artificial 
electromagnetic metasurface, and proposes a 2-bite, programmable and digital artificial 
electromagnetic metasurface. By changing a state combinationof a 
diode, the artificial 
electromagnetic metasurface unit can acquire four types of 
phase response, namely, 0, Pi second, Pi, three times of Pi second respectively corresponding to digital codes 0,1, 2 and 3. By combining a 
digital control technology, the code combination of a surface of the artificial electromagnetic metasurface can be changed, and various dynamic electromagnetic functions onthe surface of the same artificial electromagnetic metasurface can be achieved. By the artificial electromagnetic metasurface, the current situation that most of artificial electromagnetic metasurfaces lack dynamic changeable 
programming property is changed, the problem that a 1-bite programmable and digital artificial electromagnetic metasurface cannot be used for achieving reflection in different directions is solved, and the design freedom of a control electromagnetic wave of the metasurface is improved. By the 2-bite, programmable and digital artificial electromagnetic metasurface provided by the invention, electromagnetic 
information control and 
processing can be achieved, and the 2-bite, programmable and digital artificial electromagnetic metasurface has important application prospect in the field of communication and imaging.