The invention provides a non-contact photoelectrical method for detecting the form and position dimension of an iron-tower member hole, which belongs to the technical field of photoelectric detection. The iron-tower members for power transmission are mainly strip steels, and holes are perforated on the members. A manual mode is generally adopted to detect whether the holes are missed to be perforated and how the action dimensions of the holes are; therefore, the measurement precision is lower and is influenced by subjective factors of measurement operators to a large extent, the measurement precision is unstable, the weight of a measuring tool is heavy, and the detection time is long, thus the improvement on the production efficiency of large-scale workpieces is restricted. The method comprises the following steps: using a CCD image pick-up system to move linearly at uniform speed along the members and shoot continuously to transmit images to a computer image processing system; and based on a VC++ platform, performing image mosaicking, image enhancement, image drift restoration, noise removal, image binary treatment, edge extraction, central line and baseline fitting, and evaluating the distance according to fitting coordinate values to realize the non-contact photoelectrical detection of the form and position dimension of the member holes. The method is applicable to the detection of the form and position dimension of the iron-tower member holes.