[Objective] To study the response of seed germination and seedling growth of Lycium ruthenicum to PEG(polyethylene glycol)-simulated drought stress, and to provide a theoretical basis for artificial cultivation of L. ruthenicum.[Methods] PEG-6000 solution was used to simulate drought stress. Seed germination progress, germination percentage, germination potential, germination index, vital index, seedling growth, seedling osmotic adjustment substances, and chlorophyⅡ content under water stress were recorded. The effects of drought stress on seed germination and seedling growth of L. ruthenicum were studied.[Results] Drought stress was disadvantaged to seed germination of L. ruthenicum, and the severe drought stress will delay the fastigium of L. ruthenicum seed germination. Seed germination percentage and germination potential decreased with the increasing level of drought stress. Under -0.6 MPa treatment, germination percentage and germination potential decreased by 72.06% and 74.07% as compared to the one of control treatment. Germination index and vital index were restrained under drought stress, and the restraining degree increased with the increasing of drought stress. The moderate drought stress was beneficial to the growth of radicle and germ, however, it wasn't beneficial to the growth of germ under medium and severe drought stress. Proline and soluble sugar of seedling root and shoot increased with the increasing drought stress level. However, chlorophyⅡ content decreased with the increasing drought stress level.[Conclusion] Drought stress had important effect to the seed germination and seedling growth of L. ruthenicum, and the moderate drought stress was beneficial to the growth of L. ruthenicum seedling.