Carbene　polymerization　from　the　catalyzed　decomposition　of　diazo　compounds　is　a　unique　non-petroleum-based　C1　polymerization　pathway　toward　high-density　functional　polyolefins.　The　last　20　years　have　seen　vigorous　development　in　carbene　polymerization,　such　as　various　efficient　initiating　systems,　high　molecular　weight　and　stereoregular　polycarbene,　controlled　carbene　polymerization,　and　the　combined　copolymerization　approaches　with　other　polymerization　methodologies.　This　review　highlights　the　recent　advancements　in　developing　the　new/old　disciplines　of　carbene　polymerization,　i.e.,　carbene　insertion　polymerization　and　carbene　radical　polymerization.　The　representative　copolymerization　methodologies,　aggregation　structures,　properties,　and　applications　of　polycarbene　are　also　summarized.　Finally,　the　future　trends　in　expanding　carbene　polymerization　potentials　are　discussed.　©　2022　Elsevier　B.V.