A feeding experiment was conducted to examine the effects of dietary peptidoglycan on growth, non-specific immunity and disease resistance for large yellow croaker, Pseudosciaena crocea. The basal diet was supplemented with 0, 100 and 500 mg·kg^-1 peptidoglycan, respectively, to formulate three experimental diets. Each diet was fed to triplicate groups of fish in seawater floating cages (1.5 m×1.5 m×2.0 m), and each cage was stocked with 40 fish (with initial weight of (30.8±1.33) g. Fish were fed twice daily (05:00 and 17:30) to apparent satiation for 8 weeks. The water temperature fluctuated from 27.5 to 30.5 ℃, the salinity from 34 to 35‰ and dissolved oxygen content was approximately 7 mg·L^-1 during the experimental period. Results showed that survival and growth were significantly (P<0.05) affected by dietary peptidoglycan. Fish fed diets with 100 and 500 mg·kg^-1 peptidoglycan supplementation had significantly (P<0.05) higher survival (95.8% and 95.0%) than the control group (88.3%). specific growth rate (SGR) in fish fed the diets with peptidoglycan (1.44 and 1.41%·d^-1, respectively) was significantly (P<0.05) higher compared with the control group (1.21 %·d^-1). Phagocytic index (PI) and lysozyme activity (LA) of fish fed the diets with peptidoglycan were also higher than those of control group, and there were no significant (P>0.05) differences between two peptidoglycan supplementation groups. However, alternative complement pathway activity (ACH50) significantly (P<0.05) increased with increasing dietary peptidoglycan. The results of Vibrio harveyi challenge showed that the fish fed diets with peptidoglycan supplementation had significantly lower cumulative mortality (25.0% and 25.7%, respectively) than the control group (64.3%). The results suggested the dietary peptidoglycan significantly improved the growth, non-specific immunity and disease resistance of large yellow croaker. Therefore, peptidoglycan could become a safe and efficacious immunostimulate supplemented to the diets for large yellow croaker.