This study was carried out to investigate the acute oral toxicity of a crude extract derived from fruiting body of Phellinus gilvus (PGE) using male and female SD rats. Groups consisted of five male and female rats were treated with a single dose of the test substance intragastrically at 0, 500, 1,000, 2,000, and 5,000 mg/kgaj, respectively. Clinical signs, body weight change, and food and water consumption change were observed for 14 days after administration. No mortality or abnormal clinical signs in animals were shown during the observation period at the dose used in this study. Also there was no difference in net body weight gain, water and food consumption or gross pathological findings at terminal sacrifice among the groups of rat treated with different doses of the test substance. The results suggested that acute oral toxicity of PGE in rats is very low at the conditions employed in this study and $LD_{50}$ of PGE was estimated to be over 5,000 mg/$ extrm{m}{ell}$ in both sexes of rats.