The invention relates to a disposable brain state monitoring flexible patch electrode, which comprises a conductive wire, an electrode interface box, an IC (Integrated Circuit) card identification circuit, an IC card contact, an EEG ( Electroencephalogram ) acquisition and processing circuit, an Ag conductive layer contact, an electrode insert, an IC card control chip, a photographic flexible substrate film, a nano Ag circuit layer, an Ag / AgCl ion conductive coating, an insulation PE (Poly Ethylene) coating film, a collodion pad, a thorn pad and sponge. The electrode is suitable for monitoring the state of consciousness of brain, sleep or anesthesia state of a patient. The electrode adopts a film circuit printing process to coat Ag paste and Ag / AgCl paste on a photosensitive matrix material, and then the heat-curing treatment is carried out. A main electrode body is flexibly designed, and can freely bend and is not easily broken due to the strong flexibility of silver powder, and is more suitable for a human facial structure; meanwhile, the collodion pad ensures that the electrode is in contact with a human head more firmly and tightly, the sponge protects the Ag / AgCl ion conductive coating against wear, conductive paste is well accommodated and fixed, and the problems of baseline drift and waveform distortion caused by the loss of the conductive paste and the like are solved.