ABSTRACT: Purpose:We have used RNA-seq to examine of differentially expressed miRNAs in chicken leg muscle of three different development stages (11 embryo ages, 16 embryo ages, and 1 day old post hatch chick).The aims of this study are characterization of miRNAs differentially expressed in different developmental stage of chicken embryo, using RNA sequence sample. Methods: On this study we used two embryonic stage and one post hatch chick leg muscle of Xinghua chicken breed. Total RNA from E11 day embryo, E16 day embryo and 1 day post hatch chick was isolated by TRIzol following the manufacturer’s protocol (Invitrogen, CA, USA). Each stages were designed two samples, and the total samples were six (three group × two sample/group) and RNA samples of six individuals were pooled with equal amounts, and then were subjected to Illumina deep sequencing. Results: After eliminating adaptor and low-quality reads, a total of 5,302,700, 6,556,747, 5,359,793, 4,213,112, 7,112,885 and 7,469,939 clean reads were obtained in group E11 (E11.1-E11.2), group E16 (E16.1-E16.2) and group P1 (P1.1–P1.2) libraries, respectively. The clean reads were aligned to the chicken genome databases, miRBase, Rfam, RepBase and mRNA. Conclusions:To assess miRNA expression during chicken embryo skeletal muscle development, we sequenced and analyzed leg muscle at 11 day embryo age, 16 day embryo age, and 1 days post hatch.