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Pseudomonas fragi is one of the specific spoilage organisms (SSOs) in aquatic food, especially in refrigeration stage. Aiming to investigate carbon utilization of P. fragi at different temperatures and study the effect of pH value, NaCl and sodium lactate on growth of P. fragi based on the kinetics of colour formation. Firstly, bacterial suspension was inoculated in Biolog GEN III plates, respectively incubating at different temperatures (15℃, 25℃ and 33℃). Then the data were fitted by the modified Gompertz equation and kinetic parameters were estimated. Through kinetic parameters (maximum specific growth rate and lag phase), and combining utilization area (S) and average well colour development (AWCD) value, the effect of carbon source utilization at different temperatures and environment factors on P. fragiwas analyzed. Results showed that at 25℃ P. fragihad the highest carbon utilization and activity ability, which was followed by 15℃, and the lowest value was got at 33℃. At 15~33℃, P. fragi mainly used carbohydrates, amino acids and carboxylic acids. Moreover, the effect of changes of different temperatures on various kinds of carbon sources utilization was obvious, while the effect of changes of different temperatures on utilization rates was not obvious. In carbohydrates α-D-glucose, L-fucose, sucrose and D-mannitol could be better utilizated. In amino acids L-pyroglutamic acid, Dserine, L-alanine, L-glutamic acid could be better utilized. And in carboxylic acids quinic acid, D-gluconic acid, D-glucuronic acid, D-saccharic acid, L-malic acid were better utilized. At 15℃ the pH value was kept at 6.0 or 5.0, which the color maximum rates of color development were close, while at 25℃, pH value of 6.0 was far greater than at pH value of 5.0, and at 33℃ at any pH value, the growth of P. fragi was inhibited. At 15~25℃, 4%~8% NaCl and at 33℃, 1%~8% NaCl or pH value of 60 or pH value of 5.0, the growth of P. fragi was inhibited, and at 15~25℃, 1% NaCl or pH value of 6.0, pH value of 5.0 and at 33℃, 1% NaL the growth of P. fragi was promoted. The antibacterial effect on P. fragi and carbon utilization was analyzed which can provide a theoretical basis for optimizing product formulation and guaranteeing product quality.