Abstract: The TTG（tonalite-trondhjemite-granodiorite）in the western area and gneissoid adamellite unit in the eastern area of the Western Shandong Province were identified in the eastern block of the North China Craton. These two areas were amalgamated together at the latest Neoarchean along the NNW-trending paleo-structural belt with intrusion of some plutonic diorite bodies.The U-Pb SHRIMP results of zircons from the Mengshan diorite pluton in the southern segment of the paleo-structural belt give the upper interception age of 2 534±77 Ma based on the fine discordant line and give the close concordia age of 2 536±26 Ma that represents the age of diorite pluton emplacement. The diorites along the NNW-trending paleo-structural belt represent the plutonic magmatic activity and the cratonization during the juxtaposion of two Archean microblocks in the Western Shandong.