The invention discloses a preparing method of a special-shaped brass tube, and relates to copper pipe preparing methods. The method comprises the steps of burdening, smelting, ladle analysis, semi-continuous ingot casting, semi-finished product operation, heating annealing, extrusion, annealing and finished product operation. Through the stretching method, metal structure crystallization is changed, a tube is made through direct pulling, in the machining process, the heat machining temperature is 630 DEG C, before extrusion, the eccentricity is adjusted, during stretching, the machining rate is calculated, the lubricating means is adopted, during annealing, the accurate annealing temperature, time and heat preservation time can be accurately determined, through improvement of the pressureresistance, stretching and annealing technology, the European Union standard is met, the domestic blank is filled up, and the product achieves the parameters that the percentage elongation(%) is larger than or equal to 15, the tensile strength (MPa) is larger than or equal to 485, and the hardness ranges from 120 to 155.