Abstract: 【Objective】 The objective of this study is to determine the effects of different node position and boll position of fruit branch on seed germination and vigor of cotton seed. 【Methods】 Zhongmiansuo 49, Xinluzao 62 and Xinluzao 64 were selected as experimental materials and they were harvested at the appropriate time based on different node position and boll position, and the standard germination test was used to measure germination rate, germination potential, germination index, vigor index, fresh and dry weight of seedlings. Afterwards, the effects of different fruit branches and boll positions on cotton seed vigor were analyzed. 【Results】 The result indicates the seed vigor in middle fruit branch was the highest, and the seed had less germination potential, germination rate and seed vigor at upper fruit branch or lower fruit branch. The seed vigor with different fruit branches of main stem of the plant was: middle fruit branch > seed from upper fruit branch > lower fruit branch. Meanwhile, the dry weight of vegetative organs of seed seedlings in the middle fruit branch was higher than those in the upper branch and the lower branch, while the upper and the lower varied with different varieties. The effect of boll position on seed vitality showed different change patterns according to the varieties. 【Conclusion】 The middle branch on main stem of the plant produced the highest seed vigor as well as better growth seedling which is conducive to the formation of stronger seedlings, followed by the lower and upper fruit branches. In addition to that, the influence of boll position on seed vigor varies with cotton cultivars. The production of seeds with high vigor requires harvesting the central fruit branches of cotton seeds.