Abstract: The sample return mission is the most effective mission form for human beings to study major scientific problems in the universe. However, the scientific significance of a sample return mission is based on the effective protection of the sample from being contaminated by earth substances. Meanwhile, from the perspective of Earth safety, it is also necessary to prevent the biological risks of returning samples from celestial bodies that may have extraterrestrial life to the Earth. Therefore, strict sample protective measures need to be applied for a sample return mission. In This paper, we first outlined the sample protection requirements for a sample return mission; reviewed major sample protection measures of previous sample return missions taken by foreign countries, with a focus on the ongoing Mars 2020 mission; Next, we extracted four key technologies related to sample protection, including cleaning and sterilization technology for flight hardware, recontamination prevention technology before and after launch, sealed packaging technology for returned samples, and ground isolation and processing technology for returned samples. Further, we sorted out major sample protection works required in different phases of a sample return mission, and finally puts forward suggestions on sample protection for China’s future Mars sample return mission.