Global marine fishery resources are declining due to the effects of overfishing, climate change, and environmental pollution. Stock enhancement is considered to be an effective means of increasing the number of biological populations and promoting the sustainable development of fisheries. However, the effectiveness of stock enhancement is affected by many factors. Among them, the habitat conditions at the releasing waters directly affect the released fish's survival rate and growth rate. Therefore, before the fish were released in large numbers, it is important to evaluate the suitability of this water area. At present, the research on evaluating the suitability of the release waters is mainly to carry out the background investigation of the proposed releasing waters by sampling before releasing, including water quality, food organisms, fishery resources and other aspects. However, this investigation method was expensive. A small batch of Plectropomus leopardus was first released into the waters and then recaptured them in this study to develop a method for evaluating the suitability of fish-releasing waters. The growth characteristics and muscle nutrients of the recaptured P. leopardus and the farmed P. leopardus were compared to evaluate whether the waters were suitable for the growth of released fish. The results showed that the allometric growth factor b value of the recaptured and farmed populations of P. leopardus was close to 3, showing an isokinetic growth state. The growth condition factor a value of recaptured P. leopardus was more significant than that of farmed P. leopardus. The condition factor K value was also greater than that of farmed P. leopardus. There were no significant difference in moisture, crude ash, crude protein, crude fat, essential amino acid content, and total amino acid content in the recaptured and farmed P. leopardus muscles. The contents of monounsaturated fatty acids, C20:4n6, C20:5n3 and C22:6n3, in muscle of recaptured P. leopardus were significantly higher than those in farmed P. leopardus. There were no significant differences in other elements except manganese and selenium in the recaptured and farmed P. leopardus muscles. The lead content in the muscle of recaptured P. leopardus was significantly lower than that of farmed P. leopardus, and there were no significant differences in other heavy metals. In short, this study indicated that the habitat conditions of the releasing waters could ensure the balance and accumulation of various nutrients to meet the growth and development needs of P. leopardus. This study verified the feasibility of evaluating the suitability of fish-releasing waters based on the fish growth characteristics and nutrient composition and formed the evaluation process. It can provide new insight for evaluating the suitability of fish-releasing waters in the future and can also be used for other aquatic species.