The influence of the fiber loss on adiabatic compression of fundamental solitons in dispersion decreasing fiber(DDF)is investigated,and the method used to improve the adiabatic compression effect in DDF based on distributed Raman amplifiers(DRAs)has been simulated numerically. The results show that the fiber loss destroys the adiabatic compression effects in DDF;adopting the DRAs can improve the compression effects in DDF and get a higher compression factor and pulse energy;by selecting the appropriate gain parameter of 0.27/LD,a fundamental soliton with l0ps width can be compressed into a 417 fs with 5.9 times initial pulse energy,136.3 times initial peak intensity and only 2.8% pedestal energy ratio.