The utility model discloses a rotary drum washing machine uses interior barrel head structure, including discoid base member, the base member middle part is equipped with the centre bore, the evenly distributed of base member upper surface outer fringe department have three be used for with the washing machine in the barrel head water course that is linked together of bucket water course, said base member upper surface evenly is equipped with three group's drainage ways, and the drainage of every group is said and is corresponded a barrel head water course, the drainage of every group says that each drainage way is the recess of seting up at the base member upper surface including two drainage ways of symmetry setting, and a radial outer end and a barrel head water course that each drainage was said are linked together, and radial the inner that each drainage was said is faced with the centre bore mutually, two drainages during the drainage of every group is said say that the interval sets up, the base member at interval forms the separation structure. The utility model discloses an including the barrel head setting accord with water flow direction's sunken drainage structure, realize strengthening the rivers of crossing the filtration pore through waterfall mouth or filter to reach the mesh that improves water flow scouring washing and filter effect.