This paper proposes models for analyzing the security of decoy-state quantum key distribution (QKD) with state-dependent imperfections.With the privacy amplification method of QKD’s post-processing techniques

we introduce the decoy-state method used widely in QKD system to estimate the phase error rate more accurately than the case without decoy-state method.Based on this

we obtain the formula of secret key generation rates for decoy-state QKD with state-dependent imperfections

and characterize the relationship among key generation rates

state dependent parameter

detection efficiency and transmission distance.Numerical simulations indicate that the secure key generation rates’ tolerance to state-dependent imperfections decreases with the growing distance

but increases with the improving detection efficiency

which

to some extent

show the validity of the formula we obtain.