The self-priming diesel water pump set is a product with a novel structure successfully developed on the basis of repeated research on similar technologies at home and abroad. The pump set integrates self-priming and non-clogging sewage discharge. It adopts the diesel engine to drive the axial return and external mixing type, and through the unique design of the pump body and impeller flow channel, it does not need to install a bottom valve and fill water when using it. The pump set can absorb and discharge liquid containing large particle solids and long fiber impurities, and can be widely used in municipal sewage and flood control projects, agricultural irrigation, etc. The pump set has the characteristics of simple structure, good self-priming performance, strong sewage discharge capacity, high efficiency and energy saving, convenient use and maintenance, integrated and outdoor portable design, etc..