The performance of router directly impacts the Network-on-Chip (NoC) performance. This paper focus on developing efficient microarchitecture of allocator in the router and proposed matrix-diagonal allocator with high matching quality and low packets latency. The allocator, taking advantage of the fact that each element in the diagonal doesn't share the same row or column, includes matrix-diagonal virtual channel (VC) allocator and matrix-diagonal switch channel. Experimental results show that our design cannot only decrease packets latency, but also improve throughput.