The signal transducer and activator of transcription 3 (STAT3) has been shown to play key roles in cell development and apoptosis. In this study, we reported three novel single nucleotide polymorphisms (SNPs) within the STAT3 gene: AC_000176:g.45204C > T (SNP1), g.62058A > G (SNP2), and g.62230C > T (SNP3) in the second, tenth, and eleventh introns, among two Chinese native goat breeds. By using the forced polymerase chain reaction–restriction fragment length polymorphism technique, the SNPs were genotyped and we determined the minor allelic frequencies of Xinong Saanen dairy (XNSN) goats and Hainan black (HN) goats. Haplotype frequencies and linkage disequilibrium (LD) coefficients demonstrated that the CAC and CGT haplotypes had the highest frequencies, and the SNP2 and SNP3 loci had strong LD values in these breeds. Statistical analyses indicated a positive association between either a single SNP locus or and combined genotypes of two- or three-loci associations with some growth traits (P < 0.05 or P < 0.01). Next, we found the different genotypes were significantly associated with mRNA expression levels of the STAT3gene. Together, we show that the expression of STAT3 is associated with goat growth traits, which will be beneficial for animal breeding in the future.