Distributed authentication has the property of high security compared with existing authentication schemes. However, its success ratio for authentication may be not high, especially in large-scale Mobile Ad- Hoc Networks (MANETs). In order to address this issue, we propose a hybrid authentication scheme which integrates the chained authentication with the distributed authentication. When a node can't find enough authentication nodes in its one-hop neighborhood to authenticate itself, it requests its neighboring nodes to find a certificate chain to do so through the chained authentication. Hence, our scheme overcomes the drawbacks in terms of success ratio for authentication. Theoretical analysis and simulation studies show that, compared with the chained authentication schemes, our scheme is more scalable and it can increase the success ratio for authentication, without sacrificing the security requirement. Keywords: Authentication, Cryptography, Secret Sharing, Trust Transfer, Mobile Ad-Hoc Networks