Planting density affects the yield and composition of Tartary Buckwheat Jinqiao 6. The number of branches, seed number, and grain weight per plant vary with planting density. Higher density leads to lower yield. The highest yield of 2,479.67 kg/hm2 was achieved with 1,200,000 plants/hm2. Yields increase from 300,000 to 1,200,000 plants/hm2, but decline above 1,500,000 plants/hm2.