The invention provides a pipeline powder static electricity online monitoring device, comprising a material conveying pipeline communicated with a pneumatic conveying pipeline, a sealed chamber and aFaraday cylinder accommodating cavity used for placing a Faraday cylinder are formed in the side wall of the material conveying pipeline, one side surface of the Faraday cylinder is an arc plate coaxial with the material conveying pipeline, the side surface, opposite to the arc plate, in the Faraday cylinder is fixed on the outer wall of the sealed chamber, and a hole adjustable in size is formedin the bottom surface of the Faraday cylinder; an electric field induction plate is arranged in the sealed chamber, the electric field induction plate is connected with the Faraday cylinder by virtueof a conductive bolt and is fixed on the inner wall of the sealed chamber, a static eletricity tester is arranged at a position dead against the working surface of the electric field induction plate and keeping a certain distance away from the working surface, signal processing equipment is arranged outside the sealed chamber, and the signal processing equipment is connected with the static electricity tester by virtue of a wire. The Faraday cylinder taken as material collecting equipment leads a material charge signal to the electric field induction plate, and then pipeline powder static electricity is measured in real time by virtue of the static electricity tester and the signal processing equipment.