The invention discloses a 3D glass profile measuring instrument which comprises a rack mechanism, a Y-axis driving mechanism, an X-axis driving mechanism, a rotating fixing mechanism and a Z-axis detecting mechanism, wherein the rack mechanism is fixedly connected with the Y-axis driving mechanism and the Z-axis detecting mechanism through bolts, the Y-axis driving mechanism is fixedly connected with the X-axis driving mechanism through bolts, the X-axis driving mechanism is fixedly connected with the rotating fixing mechanism through bolts, the rack mechanism comprises a case bottom plate, acase outer cover and a rear cover plate are fixedly arranged at the top of the case bottom plate through bolts, and a platform supporting base and an upright post are welded at the top of the case bottom plate through bolts on the case outer cover. Through adoption of the 3D glass profile measuring instrument of the invention, a spectrum confocal sensor is used to measure the profile of mobile phone glass, and the non-contact measurement can not damage the mobile phone glass, and meanwhile, the measurement precision is high, the measurement error value is small, and the measurement time is short.