In order to obtain a method for real-time and quantitative detection of the chromium element in industrial wastewater or sewage solution, trace heavy metal element chromium in K2Cr2O7 solution is measured by laser induced breakdown spectroscopy (LIBS). The temporal evolution property and the influence of the pulse laser energies on the LIBS signal of Cr element are investigated respectively. The spectrum intensity is measured. The calibration curve of the Cr element is obtained from the measurement of the Cr 425.44 nm spectral line intensities with the Cr concentration ranging from 5×10-5 to 4×10-3. The experimental results show that the best time delay for spectrum detection is 1.28 μs and the optimal pulse laser energy is 120 mJ. The LIBS detection limit of Cr in the solution is 6×10-6 obtained from the measured calibration curve. This study indicates that LIBS can be applied to the real-time, quantitative detection of Cr element in solution with a good detection limit.