The performance of various quantum-key-distribution (QKD) systems is analyzed using 1.55 μm up-conversion single-photon detector. The dependence of quantum efficiency and dark count rate change on the pump power was also discussed. The comparison is based on the secure communication rate as a function of distance for three QKD protocols: the Bennett-Brassard 1984, the Bennett-Brassard-Mermin 1992, and the coherent differential-phase-shift keying protocols. We show that the up-conversion detector allows for higher communication rate and longer communication distance than the commonly used InGaAs/InP APD for all three QKD protocols, and the properties of quantum key distribution system can be greatly improved by this detector.