Recently,increasing evidence suggested that miRNAs contribute to the regulation of adipose deposition and fat metabolism [1-7].Meanwhile,several studies have consistently indicated that miRNAs are involved in metabolic functions of the liver,including glucose and lipid metabolism [8-12].The chicken is one kind of the most important economical animals.Until last year,789 miRNAs have been identified in the chicken genome,and the functions of a small number of miRNAs have been revealed.Some of those studies focused on chicken miRNAs only from skeletal muscles and adipose tissues at different developmental stages [13,14],but the identification of differentially expressed miRNAs in adipose tissue and liver,and their comparison between tissues and breeds,remain to be illustrated.As lipogenesis mainly occurs in the liver,and the characteristics of adipose tissue and liver are highly related with economic traits of chickens,so it is important to identify and characterize the miRNAs in the adipose tissue and liver.