With the continuous development of precision step blasting technology in open pit mines, the disadvantages of traditional layout methods in layout precision and construction efficiency are becoming more and more prominent. In order to improve the precision and efficiency of hole layout, the theory of hole layout is combined with RTK line lofting technology. According to the designed values of the chassis resistance line, hole spacing and row spacing, the RTK line lofting method is used to measure the size of the chassis resistance line and determine the line coordinates and layout direction of the first row of holes. Then, each row of holes can be laid out for construction by setting parameters such as mileage, mileage increment, deviation and deviation direction in the RTK manual book. Finally, a single person can achieve high-precision and high-efficiency hole laying while recording the hole position and measuring the design hole depth. This paper introduces a construction method of RTK line lofting and hole layout in detail, applies it to the actual construction, and gets a good effect. Applying this method provides a new idea for the precision, standardization and high efficiency of the open-pit bench blasting construction, improves the construction efficiency and precision while saving workforce, and reduces the cost of open-pit blasting.