The invention discloses an automatic pitot tube moving device with a location function and a measuring method. The automatic pitot tube moving device comprises a pitot tube, the measuring end of the pitot tube stretches into a flue to be measured, the other end of the pitot tube is located outside the flue to be measured and is driven by a driving device to drive the measuring end of the pitot tube to move in the flue, a guide fin moving along with the pitot tube is arranged at the top of the pitot tube, multiple positioning holes are formed in the guide fin, and the tail end of the guide fin and the tail end of the pitot tube are connected with a differential pressure gauge; in the direction perpendicular to the axis of the pitot tube, an optoelectronic switch transmitting end is arranged at one side of the guide fin, and an optoelectronic switch receiving end is arranged at the other opposite end. When the positioning holes move to the position of an optoelectronic switch, a light signal transmitted by the transmitting end reaches the optoelectronic switch receiving end through the positioning holes, a signal generated by the optoelectronic switch is received by a controller, and the controller controls the pitot tube to move.