The distribution features of recombinant human $alpha-interferon(rHuIFN-{alpha}A)$ and $^{14}C-radiolabeled;rHuIFN-{alpha}A;(^{14}C-rHuIFN-{alpha}A)$ were investigated in ICR mice after i.v. injection. The level of $rHuIFN-{alpha}A$ in the kidney was significantly higher than those in lung and liver at 10min after the injection. But the level was reduced significantly at 60min. The level of radioactivity in the kidney was also significantly higher than those in other organs after i.v. injection of $^{14}C-rHuIFN-{alpha}A$, but it was reduced at much slower speed than was $rHuIFN-{alpha}A$. These results show that interferon is distributed repidly and the kidney is the main site of distribution and metabolism of $rHuIFN-{alpha}A$.