Objective To explore the absorption, distribution, accumulation, and excretion after oral exposure to lanthanum and the effects of lanthanum on the blood element spectrum of rats. Methods (1) Single oral exposure experiment, 48 female SPF-grade rats were randomly divided into 8 groups with a one-time gavage of 700 mg/kg BW lanthanum nitrate solution. And the blood, heart, liver, spleen, lung, kidneys, brain, femur, and fecal of rats were collected and measured by ICP-MS after gavage for 1, 2, 4, 8, 16, 32, 64, and 128 h. (2) Repeat oral exposure experiment, another 72 SPF-grade rats were randomly divided into 4 groups, half male and female, and each group with a control and an experimental group. The experimental group repeatedly gavage lanthanum nitrate solution containing lanthanum 66 mg/kg BW, and the control group gavage an equal amount of physiological saline. Then, the 44 elements content in blood and the lanthanum content in the liver, kidneys, femur, fecal, and urine of rats were collected at 7, 14, 21, and 28 days after gavage, and measured by ICP-MS. Results After single oral exposure to lanthanum, lanthanum peaked in blood for 2 h, the elimination half-life was 69.315 h, and the overall clearance rate was 1.733 L/h/kg. Lanthanum was widely distributed in the heart, liver, spleen, lung, kidneys, brain, and femur with blood, and the level in the femur is highest (P < 0.05). The levels of lanthanum in the liver and femur were increased compared with kidneys after repeated oral exposure to lanthanum for 7, 14, 21, and 28 days (P < 0.05), and the level of lanthanum in fecal of rats was higher than that of urine (P < 0.001). Compared to the control group, the level of lanthanum was increased in the blood of rats (P > 0.05), while, there was no statistically significant difference between the control group and the experimental group in calcium, sodium, potassium, magnesium, iron, copper, zinc, selenium, cobalt, molybdenum, lead and arsenic in the blood of rats (P > 0.05). Conclusion In this experiment, lanthanum can be rapidly absorbed into the blood after oral exposure and is widely distributed in the heart, liver, spleen, lung, kidneys, brain, and femur. After repeat oral exposure to lanthanum, lanthanum is easily deposited in the liver and bones, feces excretion is the main route of elimination, and no effect of lanthanum on the blood element spectrum of rats has been observed.