We used Solexa sequencing technology to identify and determine the abundance of miRNAs and compared the characteristics and expression patterns of miRNA of 1-day-old and 36-week-old chicken hypothalamuses. We obtained 17,825,753 and 10,928,745 high-quality reads from 36-week-old and 1-day-old chickens, respectively. Three hundred and seventy-one conserved miRNAs were expressed in both libraries. Among the conserved miRNAs, 22 miRNAs were up-regulated and 157 miRNAs were down-regulated in the 36-week-old chicken hypothalamus tissues. The abundance of sRNAs between 1-day-old and 36-week-old chickens differed considerably. KEGG pathway analysis suggested that the target genes of highly expressed miRNAs in the chicken hypothalamus are associated with metabolism and development. This information on differential expression of miRNAs in the hypothalamus of 1-day-old and 36-week-old chickens will help us understand the molecular mechanisms of metabolism and development.