The invention discloses a method for casting rotary axis casts of aerogenerators, which comprises the steps of mould manufacture, the manufacture of sand moulds and moulding by casting. In the step b of the manufacture of sand moulds, a top sprue (1) is used as an inlet of iron liquor, and is alternately communicated with runners; a bottom runner is communicated with an ingate communicated with a cast mould cavity; the runners are designed into a first runner (3), a second runner (4) and a circular runner (5); the ingate is designed into a plurality of radial runners (6) for communicating the circular runner (5) and the cast mould cavity; filtering apparatuses are arranged on the first runner (3) and the second runner (4), and are also arranged between each radial runner (6) and the circular runner (5); and in the step c of moulding by casting, the casting temperature is controlled from 1310 DEG C to 1350DEG C; and finally, a cast (2) is obtained. The method for casting rotary axis cast of aerogenerator has the advantages of good residue blocking effect and low production cost.