Boric acid is a type of neutron absorber widely used in pressurized water reactor (PWR) nuclear power plants, which is added to the primary loop to control reactivity. Therefore, it is particularly important to conduct real-time and high-precision detection of boric acid concentration in the primary loop. Currently, PWRs mainly use neutron source boron meters based on neutron absorption methods, which have issues such as high radiation levels and poor accuracy at low concentrations. Laser Raman spectroscopy, due to its characteristics of being in-situ and non-destructive, has been widely applied in the spectroscopic study of chemical substances, offering the advantages of speed and accuracy. Laser Raman spectroscopy, due to its characteristics of being in-situ and non-destructive, has been widely applied in the spectroscopic study of chemical substances, offering the advantages of speed and accuracy. In traditional Raman spectroscopy quantitative methods, the concentration detection model is primarily established based on the linear relationship between intensity and concentration. The study on real-time online measurements of boric acid solution concentration shows that the SR model-based predictions for the concentration test set achieved an R2 of 0.9990, demonstrating excellent stability across different flow rate conditions. Compared with traditional methods, the precision improved from 10% to within 1.5%. When the boric acid concentration is below 1000 mg/L, the detection error remains under 15 mg/L, demonstrating long-term operational stability and high accuracy. This study develops an alternative detection method to replace neutron source boron meters, offering more stable and convenient measurement than the widely used neutron source method. This work provides a reference for applying Raman spectroscopy in boric acid detection.