LED lamp including a plurality of light guide substrate, a mounting seat, an LED lamp panel positioned on the mounting seat and having at least on LED facing an incident surface of the light guide substrate, and a diffuser enclosing the light guide substrates. Each one of the light guide substrate feature a notch configured such that the light guide substrate are coupled transverse to one another by the notches, and further include a plurality of diffused reflection elements for extracting light from the light substrate.