Salinity is an environment factor with important effects on the growth and energy allocation of brown flounder, Paralichthys olivaceus. An energetic method was used to investigate the effects of salinity manipulating on the growth and compensatory growth of juvenile P. olivaceus following salinity manipulating in the present experiment. In the experiment I, juvenile P. olivaceus with an average body weight of 2.6 g were kept in seawater with different salinities (12–S₁₂, 19–S₁₉, 26–S₂₆, 33–S₃₃, 40–S₄₀) for 30 d. In the experiment II, Juvenile P. olivaceus with body weight of 6.9 g stocked in seawater with salinity 5 (IS5), 19(IS19), and as high as 47(IS₄₇) during the first 10 d. Then the salinity was adjusted to 19 in 3 d at a steady rate and the fish experienced a recovery period of 30 d. It was found that the growth of juvenile P. olivaceus would not changed significantly within the salinity range between 12 and 40. Juvenile P. olivaceus stocked in seawater with salinity 5 (IS₅) and 47(IS₄₇) would grow significantly slower than that fish stocked in salinity of 19. Fish in IS5 achieved completely compensatory growth in 30 d after the salinity was switched to 19. But Fish in IS5 failed to catch up the weight of fish in IS₁₉. Salinity manipulating changed the energy ingestion and its allocation among respiration and feces lost, but not significantly affected the energy lost in excretion. Compare to fish in S₄₀, fish in S₁₉ allocated more energy to growth. Fish in IS₄₇ fed less than fish in IS₁₉ over the different salinity-treating period. Fish in IS₅ and IS₄₇ allocated significant lower percentages of energy to growth than IS₁₉. But the portions of respiration energy of them were significantly higher than IS₁₉. In the recovery period, IS₄₇ fed less than the other two. But the portions of growth energy were not significantly different from each other. IS₅ consumed more energy in respiration than IS₁₉ in this period. The energy lost in feces of IS₁₉ was significantly higher than others. For unit body weight daily energy budget (J·g^-1·d^-1), fish in S₃₃ fed less than S₁₂, S₁₉, and S₂₆. The highest value of unit body daily energy allocated to growth appeared in S₁₉. Daily unit body weight energy ingestion and energy used to growth were both the highest in IS₁₉ over the stressing period. The energy lost in respiration in IS₅ was higher than IS₄₇. During the recovery period, fish in IS₅ ate more than S₄₇ and allocated more energy to growth compare to IS₁₉ and IS₄₇. Unit body weight daily energy lost in feces of IS₄₇ was significantly more than other treatments over the recovery period. Studies on the composition of fish found that salinity manipulation put no significant effects on the moisture and protein content. But the lipid content and gross energy were affected by salinity manipulation. Energetic analysis indicated that the compensatory growth of juvenile P. olivaceus following low salinity stress was achieved by improved energy ingestion of feed. These results indicated that the optimal salinity for the growth of juvenile P. olivaceus would be about 19 and P. olivaceus is extremely tolerant to salinity, especially to low salinity.