Abstract : In this talk, a novel and robust quantum key distribution protocol, called the decoy-state frequency-correlated QKD (DS-FCQKD), will be proposed. This protocol considers utilizing the time-frequency entanglement of spontaneous parametric down-conversion (SPDC) photon-pairs to encode the information, its highly entangled nature has the potential to implement large-alphabet encoding and further increase the secure key rate (SKR). For the protocol’s security, our analysis shows even though Eve executes the intercept/resend (IR) attack with the optimal conditions, the decoy-state method will force Eve to send an error signal into the system which induces a considerable quantum-bit-error rate (QBER), and further ensure the security of the protocol. Since the frequency encoding of DS-FCQKD, effectively avoids the polarization mode dispersion (PMD) and phase fluctuation in optical fiber, moreover, not need interferometers. This simple setup can significantly reduce the complexity of the experimental system and has the huge potential to be implemented with realistic devices. In experimental realization, we preliminary verified the time-frequency entanglement of our source SPDC by a Franson interferometer. We observed high visibility of 94% of nonlocal interference which demonstrated the high entanglement of the source. By utilizing the optical fiber network on NCU campus, furthermore, we demonstrated the time-frequency entanglement distribution at a distance of 2.64 km. By combining the novel protocol we proposed and the developed entangled-photon-source, in the future, the scheme has a high potential toward a high-performance, robust, and practical QKD network on NCU campus.