The　level　of　human　chorionic　gonadotropin　(HCG)　is　an　important　indicator　for　early　pregnancy,　pregnancy-related　diseases　trophoblastic　diseases　and　even　cancer　diagnosis.　Therefore,　sensitive　detection　of　HCG　has　crucial　significance　in　clinical,　especially　in　gynaecology　and　obstetrics.　Herein,　a　hybridization　chain　reaction　(HCR)　assisted　multicolor　immunosensor　have　been　developed　for　HCG　analysis.　The　proposed　method　intro-duced　HCR　after　the　immunoreaction　between　antibody　and　HCG　protein,　and　produced　long　double　strand　DNA　(dsDNA)　that　contain　biotin　sites.　The　streptavidin-horseradish　peroxidase　was　linked　on　the　dsDNA　by　the　interaction　between　biotin　and　streptavidin,　and　can　further　mediated　gold　nanobipyramids　(Au　NBPs)　etching.　The　localized　surface　plasmon　resonance　absorption　peaks　of　Au　NBPs　blue　shift　and　accompanied　a　vivid　color　change　after　etching　effect.　Based　on　this　color　change,　HCG　could　be　qualitative　and　semi-quantitative　detected.　Because　of　the　introduction　of　HCR　and　enzyme　amplification　technique,　the　proposed　method　exhibited　high　sensitivity　with　a　linear　range　of　0.1-2000　pg/mL　and　limit　of　detection　(LOD)　of　0.1　pg/mL.　Finally,　the　pro-posed　immunosensor　was　used　to　detect　clinical　serum　samples.　The　results　show　there　are　no　significant　dif-ferences　between　clinical　results　and　the　test　results　by　this　method,　indicating　the　practicability　of　the　proposed　method.