The test material was the seeds of Allium mongolicum, which were unaged and artificially aged. Seeds soaking with Ce³⁺ and La³⁺ were used to determine seed germination and physiological indicators, and to explore whether the seed soaking with Ce³⁺ and La³⁺ could promote seed germination and the effect on seed vigor and physiological characteristics of aged A. mongolicum.The results showed that: (1) at 0 ~ 5 h of aging, Ce³⁺ and La³⁺ treatment could significantly promote seed germination and improve seed vitality of A. mongolicum; After 5 h of aging, Ce³⁺ and La³⁺ treatment had no significant effect on seed germination. (2) During 0-15 h of aging, antioxidant enzyme activity and AsA content in Ce³⁺ and La³⁺ treated seeds of A. mongolicum were increased, and the accumulation of O₂^-· generation rate, H₂O₂ content and MDA content were significantly decreased. After aging for 15 h, antioxidant enzyme activity of Ce³⁺ and La³⁺ treated seeds increased, AsA content decreased, O₂^-· generation rate and MDA content increased. (3) At 5 h of aging, the seed respiration rate of A. mongolicum reached the maximum, and Ce³⁺ and La³⁺ treatment significantly reduced the seed respiration rate. (4) Ce³⁺ and La³⁺ treatment increased ultraweak luminescence (UWL) intensity of A. mongolicum seeds when aging for 0-5 h, but decreased UWL intensity of A. mongolicum seeds after aging for 5 h. According to the research, in the early stage of artificial aging, Ce³⁺ and La³⁺ seed soaking can induce and enhance antioxidant enzyme activity and AsA content of seeds, effectively remove excessive ROS accumulated due to aging, reduce peroxide damage and improve seed vitality. In the middle and late stage of seed aging, the internal ROS production and clearance system was disordered, which aggravated the damage of ROS to the seed structure, and the alleviating effect of Ce³⁺ and La³⁺ infusion was lost.