Transmission characteristics of optical soliton transmission system(conventional soliton,dispersion management soliton) and quasi-linear transmission system were analyzed respectively.Conventional solitons keep the pulse shape by balancing the dispersion and nonliear effect during the transmission,but the timing jitter is severely degraded as the pusles′ high power.Dispersion management solitons solve this problem by using fibers with normal and abnormal dispersion coefficients in turn,which lower the average path dispersion while keep the higher local dispersion.But the system performance degraded rapidly by neighboring channels′ spectrum overlapping as the pulse width is always limited in one bit slot.So dispersion management soliton is proper for single channel high speed long haul transmission.Different with soliton transmission,quasi-linear transmission control the nonliear as a harmful effect,and keep the average path dispersion around zero by strongly dispersion management,so the spectrum width is degraded dramatically,and so do the nonlinear interaction among the channels.As this reason,quasi-linear transmission is suitable for high speed long haul wavelength division multiplex transmission.