The utility model relates to an arranging structure of a cooling water pump, in particular to an arranging structure of a cooling water pump of a single-cylinder water-cooled diesel engine, and belongs to the technical field of diesel engine cooling water pumps. The arranging structure comprises the cooling water pump, one end of an impeller shaft of the cooling water pump is connected with a water pump connector which is connected with a flywheel through a bolt, one end of a water returning pipe is connected on a water returning port of the cooling water pump while the other end of the same is connected with a water outlet of a heat radiator, a cylinder cover and a cylinder sleeve are arranged on a diesel engine shell, a water inlet of the heat radiator is connected with a cylinder cover water outlet on the cylinder cover through a second water incoming pipe, a water sleeve is arranged in each of the cylinder cover and the cylinder sleeve, the water sleeve of the cylinder cover is connected with the water sleeve of the cylinder sleeve through a water feeding pipe, the water sleeve of the cylinder sleeve is connected with one end of the first water incoming pipe, and the other end of the water incoming pipe is connected with the water outlet of the cooling water pump. The arranging structure is reasonable in design, convenient to mount and high in transmission efficiency, and difficulty in arranging the whole single-cylinder water-cooled diesel engine is lowered.