The mitochondrial DNA of 172 sheep from 48 families were typed by using PCR-RFLP, direct amplification of the repeated sequence domain and sequencing analysis. The mitochondrial DNA from three lambs in two half-sib families were found to show paternal inheritance. Our findings provide direct evidence of paternal inheritance of mitochondria DNA in sheep. A total of 12 highly polymorphic microsatellite markers, which mapped on different chromosomes, were employed to type the sheep population to confirm family relationships. Possible mechanisms of paternal inheritance are discussed.