Abstract: Researches were conducted on the inter-population and intra-population variation of seeds of 12 representative natural Aleuvites fordii populations in Sichuan and Chongqing areas. Ststistical analysis such as variance analysis,multiple comparison,variation coefficient comparison,repeatability comparison and correlation analysis were adopted to explore the character of fourteen kinds of seeds. The results showed that the intraspecific seed character of inter-population and intra-population of Aleuvites fordii had plentiful variations. The variation of seed morphology was more stable than that of fruit morphology. The variation coefficient of seed morphology ranged from 6.43% to 74.93%, with the average of 25.74%, which showed that variation of intra-population(74.26%) was higher than that of inter-population.