The study investigated the developmental changes of Myoglobin (MB) in muscles of Jinhua pig (China s fatty breed) and the breed differences between Jinhua and Landrace (lean) pigs. About 30 Jinhua and Landrace barrows (three of each breed, at birth, age 60, 90, 120 and 150 days) were used to detect the postnatal growth changes of MB, peroxisome proliferator-activated receptor gamma, co-activator 1 alpha (PPARGC1A) and Peroxisome Proliferator-Activated Receptor Delta (PPARD) mRNA expression and soluble MB concentration (SM) in M. Longissimus Dorsi muscle (LD). Results showed that MB and PPARD mRNA expression in LD were significantly affected by ages of pig and PPARGC1A mRNA expression in LD was lower at birth and significantly higher from age 60-150 days (p<0.05). The differences of MB, PPARGC1A and PPARD mRNA expression and SM in LD between two pig breeds were also investigated. The data showed that MB and PPARD mRNA expression and SM in LD of Jinhua barrows were significantly higher (p<0.05) than that of Landrace barrows from 60-150 days but no significant difference at birth and PPARGC1A mRNA expression were similar but the age was only at 120 days (p<0.01). At last, MB, PPARGC1A and PPARD mRNA expression and the correlation among gene, protein, CIE (a uniform colorimetric system defined by the Commission Internationale de l Eclairage) and pH were evaluated. The data showed that the correlation between MB, SM, PPARGC1A and PPARD mRNA expression in LD were high and the correlation coefficients between MB and SM, PPARGC1A, PPARD, CIE L* and CIE a*-values were 0.81, 0.44, 0.81, -0.26 and 0.69, respectively. Correspondingly, the correlations between SM and PPARGC1A, PPARD, CIE L*, CIE a* were 0.44, 0.74, -0.26 and 0.73, respectively. In summary, the study is the first one which was conducted to explain the postnatal growth changes of MB mRNA expression in skeletal muscles of Jinhua pigs and provides information for development of nutritional methods to regulate MB in regulating and improving meat quality.