Soil compaction by agricultural machinery has become one of the most serious soil degradation problems in the world. This paper reviewed the research progress of soil compaction from four aspects: detection, impact, alleviation and prevention of soil compaction. It shows that new detecting methods are urgently needed for field soil compaction detection. The impact of soil compaction is mostly focused on the top cultivated soil layer, but the effects of subsoil compaction and its potential ecological services in addressing climate change have been overlooked. Reasonable agricultural management strategies such as crop and tillage rotation methods could be applied to alleviate soil compaction. Overall, subsoil compaction is difficult to alleviate in a short period and prevention should be the top priority although there is still a lack of practical prevention methods. Agricultural mechanization in China is still in the early development stage, and effective preventive measures should be taken to avoid soil compaction like that in developed countries.