Based on conventional observation data, typhoon best-track dataset, gauge-satellite-radar combined hourly precipitation products (0.05°×0.05°), black-body temperature from FY-2G satellite (0.1°×0.1°), and NCEP／NCAR FNL reanalysis data (1°×1°), the heavy rainstorm in Shandong on 11 August 2019 triggered by Typhoon LEKIMA is analyzed. The results are listed as follows. 1) The heavy precipitation is mainly affected by typhoon inverted trough that maintains for a long time in the rainstorm area in the central part of Shandong. The low-level southeast jet on the east side of the typhoon transports the water vapor and energy in the north of East China Sea to the rainstorm area, and combining with the pumping action of upper-level jet stream at 200 hPa, the water vapor converges and is lifted over the rainstorm area, which jointly result in the rainstorm with mesoscale characteristics. 2) The positive vorticity area in the rainstorm area is accompanied with strong ascending motion by the configuration of low-level convergence and high-level divergence and the coupling of secondary circulation, which provides favorable dynamic conditions for the typhoon rainstorm, and the dynamic conditions are more important than thermal conditions for the rainstorm process. 3) The water vapor flux convergence center at 850 hPa and corresponding vertical area of strong ascending motion have a good indication for predicting the heavy precipitation area and intensity.