Physiological and biochemical indices of blood from pond- and indoor tank-cultured Japanese flounder Paralichthys olivaceus were analyzed and compared in the present study. Four groups of fish at different body weights from pond-culture (PSJF, pond-cultured small Japanese flounder group and PBJF,pond-cultured big Japanese flounder group) and indoor tank-cultured (ISJF,indoor tank-cultured small Japanese flounder group and IBJF,indoor tank-cultured big Japanese flounder group) were sampled respectively, then 5 blood physiological indices and 13 serum biochemical indices were determined. Results revealed that the amount of red blood cells (RBC) of PSJF and PBJF were significantly lower than that of ISJF and IBJF (P < 0.05), and erythrocyte sedimentation rate (ESR), erythrocyte fragility (EOF), the amount of white blood cells (WBC), and lymphocyte proportion of leukocyte in blood were significantly higher in pond-culture fish (P < 0.05). Besides, serum glucose(GLU), total protein(TP), albumin(ALB), globulin(GLO), creatinine(CREA), cholesterol(CHOL), triglyceride(TG) concentrations and alkaline phosphatase(AKP) activity ofPSJF and PBJF were significantly higher than those in ISJF and IBJF (P < 0.05). However, serum lactate dehydrogenase activity of PSJF was significantly lower than ISJF (P < 0.05). Statistical analysis revealed no significant differences in serum chloride (Cl-) concentration, calcium (Ca2+) concentration, alanine aminotransferase (ALT) activity and aspartate aminotransferase (AST) activity among all the groups (P > 0.05). The results showed that pond-cultured Japanese flounder may have lower requirement for the respiratory metabolism than indoor tank-cultured Japanese flounder, whereas serum immunity level and nutrition metabolism level may be higher. These results may provide basic information on management of pond-cultured and indoor tank-cultured Japanese flounder.