Abstract: In a 9-to 11-year-old Live oak (Quercus virginiana) plantation with density of 1 200 trees per hectare, which located at the sandy saline soil of Shangyu District, Shaoxing City, Zhejiang Province, the fallen seeds from 3542 trees randomly selected were periodically collected and weighted from October to January for three years. The variation and stability of annual seed yield, fall-off rhythm, seed size and form characteristic of same trees were studied. The mean seed yields per tree in 2012, 2013 and 2014 were 2.32 (0.00~8.51) kg, 1.38 (0.03~5.61) kg and 2.92 (0.40~6.58) kg, respectively. The process from beginning to closing of seed dropping for a plantation lasted as long as 80~100 days, and they were highly coincident with Logistic model. The 69.79%~82.56% of annual seed yield were fallen within 40 days from first 10 days of November to that of December. The seed yield of the 26 trees showed extreme variation among individual trees and years (P≤ 0.001 3), and the annual variation coefficient of individual seed yield ranged from 9.78% to 138.76%. The early and late orders of initial, peak, and closing period of seed dropping displayed notable differences among individual trees and years (P≤ 0.000 5), and higher year correlations (r=0.42~0.67). The 100-seed-weight, seed width, seed length and form index (length/width) showed significant differences among trees (P≤ 0.000 4), but not between years. The yearly correlations were higher (r=0.64~0.87), and the seed form was the most stable character. The researches indicated that the Live oak plantation aged about 10 had fairly high seed production capacity, but the differences of seed yield among individual trees were huge, and unstable year correlations. Variations of seed fall-off period and seed size were extremely rich and with high year stability.Through long-term observation, some types of mother tree with relatively stable high or low yielding, and early-or late-maturing could be recognized and selected.