The structural characteristics and precipitation differences of mesoscale convective complexes (MCCs) affecting Shandong are analyzed using satellite data, routine observations and ERA5 (ECMWF Reanalysis v5) data from 2007 to 2022. The results are listed below. (1) Most MCCs, developing and maturing from the evening to the early morning of the next day and then disappearing in the morning, have a long life history with an average lifespan of 7 h and 88% of 6-8 h. Based on the generation sources and moving paths of convective cloud clusters, MCCs can be classified into three types, namely eastward type, northward type and in-situ generating type, with the eastward type being the most frequent. (2) The strong precipitation in MCCs is closely related to the minimum cloud top brightness temperature (also referred to as black body temperature, TBB) and the areas of large TBB gradient. The 500-hPa circulation of the eastward type in the mid-high latitudes is flat, and the strong precipitation is located on the west-northwest side of MCC; the circulation of the northward type is meridional, with the strongest precipitation located on the south-southwest side of MCC; the in-situ generating type has weak guiding airflow, scattered distribution and small range of precipitation and the precipitation is distributed in the areas of large TBB gradient. (3) The strong convergence of cold and warm air in the eastward type and northward type leads to frontogenesis, the strongest area of frontogenesis in the warm advection zone usually corresponds to the center of large precipitation, and there is no significant precipitation in the frontolysis zone. However, the cold advection of the in-situ generating type is weak, and the strong precipitation is mainly located on the warm side.