The invention relates to an American ginseng prescription for treating nephritis. The prescription comprises the following components in percent by weight: 3-5% of American ginseng, 3-5% of bird's nest, 3-5% of Phymatodes crentopinnata (Clarke) Ching, 80-85% of chicken soup and 5-10% of rock candy. The prescription is prepared by the following steps: cutting the American ginseng into shreds, swelling the bird's nest, washing the Phymatodes crentopinnata (Clarke) Ching, crashing the rock candy, putting into the chicken soup altogether and stewing with slow fire for 120 minutes. The prescriptioncan be taken twice one day, the soup is for drinking, and the ginseng and the bird's nest are for eating.