Abstract: In light of the entry descent and landing flight in Chinese Mars exploration mission,this paper has analyzed the difficulties of this mission phase based on the characteristics of Mars atmosphere and terrain. All the past soft landing missions on Mars have been reviewed and the potential reasons for mission failure have been summarized. The communication architecture in Mars Science Laboratory has been introduced to illustrate all the potential communication methods. The key technologies include communication strategies for blackout,selection of signal modulation and high dynamic signal detection at low SNR. Finally,suggestions have been proposed for the implementation of EDL flight in Chinese Mars Exploration missions.