Selenium is an essential trace element for humans, with rice being a major dietary source. Different rice varieties respond differently to selenium, affecting selenium enrichment. This study investigated the effects of humic acid selenium on seed germination, seedling growth, and physiological characteristics of three rice varieties: Qiantaiyou 851, Qianliangyou 1606, we used the thiobarbituric acid colorimetric method to determine malondialdehyde content and the guaiacol method to measure peroxidase activity, aiming to clarify their interactions and guide selenium-enriched rice cultivation.Results showed varietal differences in responses. Humic acid selenium improved germination rates, especially in Qianyouxiang 88, while Qianliangyou 1606 maintained the highest rate. It promoted seedling growth in Qianyouxiang 88 (height and stem diameter) and Qiantaiyou 851 (root length) but inhibited growth in Qianliangyou 1606. Peroxidase (POD) activity increased, and malondialdehyde (MDA) content decreased in all varieties, with the most significant changes in Qiantaiyou 851. Qianyouxiang 88 showed strong antioxidant capacity after treatment. These results support variety selection and technical improvement for selenium-enriched rice cultivation.