In order to study the performance of frequency transfer based on fiber link, the impact of the transfer delay fluctuation upon the frequency transfer stability is analyzed. It is found that the transfer delay fluctuations caused by the variations in refractive index, the variation in fiber link length, and the excursion in laser output wavelength are major factors reducing the stability of frequency transfer. Using the newly established round-trip timing sequence model, it is shown that the transfer delay fluctuation resulting from temperature slow variation can be compensated, but the transfer delay fluctuation caused by temperature fast variation cannot be compensated. Reducing the rate of the dynamic junction temperature variations of laser is an effective method to improve the stability of frequency transfer. In order tosatisfy the requirement that the short term stability and long term stability are less than 10-15 s-1 and 10-20 d-1, respectively, some effective measure, must be taken and the rate of the dynamic junction temperature variations of laser must be precisely controlled to be less than 0.04 ℃/s.