There are two types of diamond ores, the primary diamond ore and the alluvial diamond ore, with industrial value in the western Shandong Province. Diamond- bearing mother rocks of primary diamond ores are mainly kimberlite and lamprophyre. Diamond- bearing mother rocks of alluvial diamond ores are conglomerate and sandstone occurring in the Quaternary Xiaobuling and the Yuquan Formations. The Cambrian Liguan, the Carboniferous Benxi, the Jurassic Santai, the Neogene Baiyan Formations and the Paleogene Guanzhuang Group are also diamond- bearing strata, but do not meet the industrial utilization requirement. Compared to the diamonds contained in these reservoirs, the diamond particle size in the Mengyin and the Feixian of the Benxi Formation is the largest, the diamond content in the Pingyi- Sishui area of the Baiyan Formation is the richest, the proportion of complete crystal shape in the Linyi Jinqueshan of the Santai Formation is the highest, and the erosion and roundness in the Zaozhuang Shangnihe and the Sishui Xuezhuang area of the Liguan Formation are most prominent. Different strata and types of diamond indicate different source regions, formation age and tectonic background. Lithofacies and paleogeography analyses show that the diamonds of the Liguan Formation originated from southwest of ultramafic rocks in the Early Precambrian crystal basement of the Mashan- Sihaishan region. These ultramafic rocks were formed in the Neoarchean followed by the Early Precambrian crystal basement uplift in the Late Proterozoic. The ultramafic rocks thereafter underwent denudation. Finally, a small amount of diamonds were deposited in the Liguan Formation conglomerates at the base of the Cambrian. The distribution and characteristics of diamonds in the Benxi and the Santai Formations indicates that the source region is the Mengyin kimberlite. The kimberlite in the Mengyin was formed in the Early- Middle Ordovician. After the formation of kimberlite, the Caledonian and Indosinian Movement- the Early Yanshan Movement resulted in the uplift of the Culaishan- Mengshan district. Afterwards, the kimberlites were lifted to the surface and denuded, and the diamonds were deposited in conglomerate of the Benxi and Santai Formations. The distribution and characteristics of diamonds in the Guanzhuang Group,and the Baiyan, the Xiaobuling and the Yuquan Formations indicates that they also mainly come from the Mengyin kimberlites. The Cenozoic Culaishan- Mengshan in the north of the western Shandong Province is still in a strong uplift state, which results in the distribution of the Baiyan, the Xiaobuling, and the Yuquan Formations diamond enrichment areas in the south of the western Shandong Province. The geochemical characteristics of the diamond source region in different ages indicates chemical evolution of mantle. North China block from Archean to Paleoproterozoic mantle source region with ε Nd ( t ) value from +0. 5 to +4 indicates that the upper mantle is in a weak deficit condition. The ε Nd ( t ) value of kimberlite in the western Shandong Province varied from -4. 78 to +2. 76, suggesting that the Paleozoic mantle was in a state of weak enrichment. The ε Nd ( t ) value of Mesozoic mafic rocks in the western Shandong Province varied from -9. 2 to +21. 21, suggesting that the Mesozoic mantle was in a state of strong enrichment. Diamond deposits in kimberlite pipes were derived from the early Paleozoic weakly enriched mantle in the western Shandong Province.