The network topology is the foundation of data center networks, and it is directly related to the performance, management, operation, maintenance and many other aspects of data center networks. With the rapid growth of cloud computing, the demand for high bandwidth and low network latency increases greatly. Traditional tree-based topologies of data centers have some inherent problems such as poor scalability, the lack of path diversity, low bisection bandwidth, etc. In this paper, we propose a new optical interconnection topology for data centers, which is called OIT. In our theoretical analysis, OIT has good characters of scalability and path diversity. We also design a new routing algorithm according to its network features.