The autocorrelation function of the output polarization states of the optical transmission links in presence of polarization mode dispersion (PMD) and polarization dependent loss (PDL) was investigated by theory and Monte-Carlo simulation method. An analytical expression for the autocorrelation function was obtained by theory, and it is fit well with the result of the simulation. The results show that the bandwidth of the normalized autocorrelation function increases with increasing the polarization dependent loss, and the bandwidth decreases with increasing the polarization mode dispersion.