In order to study ovine follistatin function, we amplified the total of 1 038 base pair of ovine complete follistatin cDNA and cloned into pGEM-T vector by RT-PCR from ovine ovary RNA. After removal of the signal peptide it was subcloned into the pET41a to construct the prokaryotic expression vector, named pFSsig?. SDS-PAGE and Western blotting identified the 66 kDa product of the expression of follistatin cDNA. Based on the complete CDS sequence, we cloned follistatin N-terminal domain and domain 1 with PCR and inserted into pLEX-MCS lentiviral vector, named pFS-N+D1. After package and passage of lentivirus in 293T cells, and then infected sheep primary muscle cells (SPMC). The expression of FS N+D1 in SPMC was assayed by Western blotting. The cell growth curve of the infected SPMC and noninfected control cells displayed that FS N+D1 stablly transfected SPMC proliferated significantly faster than the control cells (P<0.01). Our data inferred that ovine FS N+D1 domain had the function to stimulate sheep muscle cell growth.