A microcosm incubation experiment was conducted to investigate the effects of earthworm (Eisenia fetida) mucus on the growth of ryegrass seedling and uptake phenanthrene. The tested soil was artificially spiked with phenanthrene (50 mg/kg) and 2 treatments (ryegrass inoculated with and without earthworm mucus) were set up. According to the different concentrations of earthworm mucus, 2/8, 3/8, 1/2 and 1 of the concentration of the original earthworm mucus were set up as the treatments. Results showed that: 1) earthworm mucus significantly enhanced the growth of ryegrass seedling, with the fresh weight biomass of root shoot and the total ryegrass seedlings increased by about 33.6%-146%, 12.4%-35.8% and 34.5%-59.6%, respectively; 2) remarkably lowered the phenanthrene concentration in root of ryegrass by approximately 23.0%-49.0%, and elevated phenanthrene uptake of ryegrass by approximately 62.8%; and 3) reduced root concentration factors and improved the translocation factor by about 33.7%-52.6% and 54.0%-102.0% respectively.