Abstract: To address large variability in size of main peanut varieties grown in Henan Province, which leads to a large variability in seed discharging qualification rate and poor adaptability in the same seed discharger, it is necessary to investigate filling characteristics and optimal speed of seed discharging in internal seed filling type seed discharger for different varieties of peanut seeds．Using Yuhua 37, Yuhua 65 and Yuhua 9326 as experimental research objects, triaxial dimensions of seeds were measured, and differences and distributions of their main parameters such as mean diameter, coefficient of variation and sphericity were calculated and analyzed．The EDEM software was used to simulate filling characteristics of different varieties of peanut seeds during discharging process of internal seed filling and discharging device．Test results showed that Yuhua 37 and Yuhua 65 had the highest double seed rate and the best filling performance at seed rower speed of 25 r/min, with double seed rate reaching 83.89% and 89.56%, respectively; Yuhua 9326 had the highest double seed rate and the best filling performance at seed rower speed of 15 r/min, with double seed rate of 81.99%．Validation tests were conducted on peanut seeds of Yuhua 37, Yuhua 65 and Yuhua 9326 under the best rower speed conditions, and results showed that double grain rate of rower seeds were 82.17%, 84.31% and 89.75%, respectively, with a maximum error of 0.42% from simulation results．Using simulation tests on different varieties of peanut seeds under different rotational speed conditions, the best rotational speed parameters were determined, and the maximum error between them under the same conditions was 0.42% by conducting verification tests on the best parameters and comparing them with simulation test results, indicating that simulation tests could be used for design and optimization of seed rower parameters to improve its research and development and research progress and reduce processing and manufacturing costs．Meanwhile, different speed adjustments should be made for different varieties of peanut seeds to improve quality of seeding．