Marine sediments contain large amounts of alkanes， mainly consisting of methane （CH₄）， ethane （C₂H₆）， and propane （C₃H₆）. Similar to methane， ethane and propane are also important greenhouse gases. The decomposition of hydrates and oil/gas seeps can cause the release of ethane and propane into seawater and the atmosphere， significantly impacting the marine ecosystems and global climate change. The microbial oxidation of alkanes， in marine environments， effectively reduces the emission flux of these gases. The latest research progresses on the distribution and biotransformation of ethane and propane in marine environment were reviewed with the following highlights： \mathrm{①} The distribution of ethane and propane in seawater exhibited clear patterns， which are largely influenced by hydrological， chemical， and biological factors； \mathrm{②} Biological sources of ethane and propane in marine environments include phytoplankton production in seawater and anaerobic production by microorganisms in sediments. Methanogens can produce ethane and propane using a variety of substrates， and \mathrm{③} aerobic oxidation of ethane to propane is performed by hydrocarbon-degrading bacteria， and this process is accompanied by carbon and hydrogen isotope fractionation. \mathrm{④} Anaerobic oxidation of ethane and propane in sediments is usually coupled with sulfate reduction. Sulfate-reducing bacteria can oxidize ethane and propane， and a possible mechanism for this process has been proposed. This review summarizes the source， distribution， and microbial metabolism of ethane and propane in marine environments and provides a scientific basis for further understanding the biogeochemical cycle of hydrocarbons.