The invention discloses an electric power maintenance electronic warning board stable to assemble and convenient to adjust and assemble. The electronic warning board comprises a digital display plate,a warning assembly machine body, a sealing pad, an assembly cover and a warning board assembly head. When the electronic warning board provided by the invention is used, 1, by virtue of a drawing-pressing or ejecting-pressing trigger mechanism which is subjected to synchronous running with a linkage switch, in coordination with a lifting clamping rod and a clamping groove mechanism at an adjusting connector, the equipment, through positive pressure and negative pressure which are generated when the equipment is used, can drive the clamping rod to lift so as to locking the adjusting connector,so that the equipment, on the basis of being adjustable, can achieve unchanged direction when used, and influence of weathers, touch by mistake and the like to the use of the warning board can be avoided; and 2, by virtue of an assembling head which is provided with a rubber inner ring, in coordination with the drawing-pressing or ejecting-pressing trigger mechanism, the equipment can be installed in two modes, namely extruding cladding and negative-pressure adsorbing, so that the installing stability of the equipment can be guaranteed better, influence of wind blowing and the like to the installing stability of the equipment can be prevented better and safety can be guaranteed.