Natural　products,　especially　bioactive　molecules　as　drug　lead　compounds,　have　attracted　extensive　attention　in　health　promotion　and　in　drug　discovery　and　development.　It　is　essential　to　understand　the　structures　and　functional　mechanisms　of　these　lead　molecules　prior　to　drug　development.　This　review　provides　comprehensive　information　for　more　than　130　newly　reported　peroxides　appeared　in　the　literature　in　the　recent　years.　The　compounds　are　natural　peroxides　with　bioactivities.　While　some　of　them　appeared　in　previous　reviews,　a　great　number　of　newly-found　natural　peroxides　with　up-dated　information　are　extensively　reviewed　in　this　article,　which　focuses　on　the　biological　activities　based　on　various　structural　classes　including　monoterpenoids,　sesquiterpenoids,　diterpenoids,　sesterterpenoids,　triterpenoids　and　steroidal　peroxy　compounds　isolated　from　terrestrial　and　marine　sources.　These　natural　peroxides　are　valuable　sources　in　drug　discovery　with　antitumor　and　antimalarial　activities.