The invention relates to a powder phase concentration measurement device. The powder phase concentration measurement device comprises an upper cylinder body, a lower cylinder body and a fixing and connecting part, wherein the upper barrel body is of a through barrel-shaped structure and is provided with an upper opening allowing powder to flow in and a lower opening allowing the powder to flow out, and at least one detection sensor is arranged on the inner wall of the upper barrel body; the lower barrel body is of an elbow structure with a U-shaped section, and a main body part of the lower barrel body is obliquely connected with the lower opening side of the upper barrel body in a stipulated angle; the fixing and connecting part is arranged at one end, opposite to a part where the lower barrel body is connected with the upper barrel body, of the lower barrel body. According to the structure, the phase concentration of powder in a pneumatic transmission environment can be accurately measured, so that the dielectric constant calibration is carried out according to the measured phase concentration.