Several recent studies investigated the role of the miR-29 family in muscle development. However, only a few studies focused on chicken skeletal muscle. In the present study, cell cycle, 5-ethynyl-2’-deoxyuridine (
EdU
), cell counting kit-8 (
CCK-8
), and other assays indicated that miR-29b-1-5p can inhibit the proliferation of chicken primary myoblasts (
CPMs
); the western blot assay and immunofluorescence detection of MYHC demonstrated that miR-29b-1-5p can promote the differentiation of myoblasts. The functional enrichment analysis revealed that the target genes of miR-29b-1-5p may be involved in muscle tissue development, muscle organ development, and striated muscle tissue development, which are biological processes related to muscle development. The correlation analysis showed that these 6 genes, that is, ankyrin repeat domain 9 (
ANKRD9
), lactate dehydrogenase A (
LDHA
), transcription factor 12 (
TCF12
), FAT atypical cadherin 1 (
FAT1
), lin-9 homolog (
LIN9
), and integrin beta 3 binding protein (
ITGB3BP
), can be used as effective candidate target genes of miR-29b-1-5p. Moreover, miR-29b-1-5p inhibits the expression of
ANKRD9
by directly binding the 3′UTR of
ANKRD9
. Overall, these data indicate that miR-29b-1-5p inhibits the proliferation of primary chicken myoblasts, stimulates their differentiation, and is involved in the process of muscle development and that its effective target gene is
ANKRD9
. This study identified the molecular mechanism of miR-29b-1-5p in chicken muscle development.