Abstract: In order to study the effects of Tebeigai soil conditioner on the yield and selenium content of ryegrass（Lolium perenne L.） in selenium-rich soil, a single-factor randomized block field plot experiment was conducted. Five treatments were set according to different application amounts of Tebeigai soil conditioner: CK（0）, T₁（750 kg/hm~2）, T₂（1 500 kg/hm~2）, T₃（2 250 kg/hm~2） and T₄（3 000 kg/hm~2）. Each treatment was repeated three times. At 60, 90 and 120 days after sowing, ryegrass was mowed to determine hay yield, selenium content, and some heavy metal content（arsenic, lead, mercury, cadmium, chromium）. Correlation analysis of selenium and heavy metal contents in ryegrass was carried out by Pearson product distance correlation coefficient. The results showed that: the hay yield of ryegrass in T₁, T₂, T₃ and T₄ were 10 205.86 kg/hm~2, 9 581.72 kg/hm~2, 9 682.35 kg/hm~2 and 9 315.12 kg/hm~2, respectively. Compared with CK（8 908.81 kg/hm~2）, they were increased by 14.56%（P＜0.05）, 7.55%（P ＞ 0.05）, 8.68%（P＞0.05） and 4.56%（P＞0.05）, respectively. The selenium content of ryegrass plants at T₁, T₂, T₃ and T₄ were 0.046 mg/kg, 0.050 mg/kg, 0.045 mg/kg and 0.040 mg/kg, respectively. Compared with CK（0.033 mg/kg）, they were increased by 39.39%（P＞0.05）, 51.52%（P＜0.05）, 36.36%（P＞0.05） and 21.21%（P＞0.05）, respectively. Among them, fertilization T₂ had the best effect on improving selenium content of ryegrass. The contents of arsenic, lead, mercury, cadmium and chromium in ryegrass of different treatments were all lower than the reference values（Feed Health Standard GB 13078—2017）, and the differences were not significant（P＞0.05）. There was no significant correlation between selenium and the contents of arsenic, lead, mercury, cadmium and chromium of ryegrass（P＞0.05）. The results indicated that the yield and selenium content of ryegrass could be increased by applying proper amount of soil conditioner Tebeigai in selenium-rich soil, and the appropriate application amount was 1 500 kg/hm~2.