Abstract: Selecting suitable stubble height is one of the key techniques for machinery-harvested ratoon rice. By using rice cultivar “Neiyouhang148” as test material, and designing four treatments of stubble heights, i.e. 5 cm, 15 cm, 25 cm and 35 cm, the test on machinery-harvested stubble height of ratoon rice at the first cropping season were carried out. The results showed that, when stubble height was 25cm, the treatment had the maximum tillers number, more effective panicle number and rational panicle-spikelet structure, the yield reached to 372.4 kg/667 m², and the yield increased by 71.7 kg/667 m²(1075.5 kg/hm²), 53.6 kg/667 m²(804.0 kg/hm²) and 26.8 kg/667 m² (402.0 kg/hm²) to compare with the treatments of 5 cm, 15 cm and 35 cm respectively; the treatments with stubble height 25 cm and lower, the harvesting time could be adjusted to the same time in rolling area and no-rolling area.