As　an　important　complement　to　traditional　mechanical　connections,　bonded　structures　are　widely　used　in　industry.　Under　the　combined　effect　of　external　loads　and　environmental　factors,　the　performance　of　the　bonding　interface　will　deteriorate,　which　seriously　affects　the　safe　use　of　bonding　structures.　Therefore,　the　performance　evaluation　of　bonding　interfaces　has　always　been　a　hot　and　difficult　issue　in　the　field　of　non-destructive　testing.　Traditional　linear　ultrasonic　technology　can　effectively　detect　damage　such　as　delamination　and　debonding　in　the　bonding　interface,　but　it　is　difficult　to　detect　and　quantitatively　evaluate　the　early　degradation　of　the　bonding　interface　(such　as　closed　defects　and　weak　bonding).　However,　the　nonlinear　ultrasonic　technology　can　overcome　the　low　sensitivity　of　the　traditional　linear　ultrasonic　technology　and　is　expected　to　be　an　effective　means　for　nondestructive　testing　of　early　deterioration　of　bonding　interface　performance.　In　this　paper,　we　review　the　recent　development　of　nonlinear　ultrasonic　technology　for　bonding　interface　detection　from　theoretical　models　and　testing　experiments.　From　the　perspectives　of　contact　nonlinearity　of　the　interface　and　material　nonlinearity　of　the　interlayer,　we　introduce　relevant　theoretical　models　for　nonlinear　ultrasonic　inspection　of　bonded　interfaces,　such　as　nonlinear　spring　model,　interface　contact　model　and　contact　model　considering　the　thickness　of　the　interlayer.　These　models　can　be　used　for　the　description　of　various　acoustic　nonlinear　effects　(such　as　second　harmonic　generation,　wave　mixing　and　nonlinear　resonance)　generated　by　ultrasonic　waves　at　weak　bonding　interfaces,　but　the　ability　of　different　models　to　characterize　the　nonlinear　propagation　behavior　of　ultrasonic　waves　at　weak　bonding　interfaces　needs　to　be　further　investigated.　Meanwhile,　we　review　the　progress　of　three　nonlinear　techniques　of　nonlinear　ultrasonic　resonance,　wave　mixing　and　second　harmonic　generation　in　the　experimental　testing　of　bonding　interface　properties.　The　nondestructive　testing　of　bonding　interface　using　nonlinear　ultrasonic　resonance　technique　remains　relatively　limited.　Mixing　technology　is　of　great　interest　because　of　its　flexibility　and　selectability　of　excitation　frequency,　mode　and　area　of　action,　and　its　ability　to　effectively　avoid　the　effects　of　system　nonlinearity.　Among　the　nonlinear　ultrasonic　methods,　harmonic　techniques　are　the　most　widely　used,　and　have　been　used　for　damage　detection　and　performance　evaluation　of　bonding　interfaces,　such　as　bonding　thickness　measurement,　debonding　detection,　bond　strength　and　fatigue　life　evaluation.　The　harmonic　technique　is　considered　as　a　possible　solution　for　the　quantitative　detection　of　the　interface　properties　of　multilayer　bonded　structures.　However,　how　to　distinguish　the　harmonics　generated　by　weakly　bonded　interfaces　from　those　generated　by　detection　systems　has　been　a　challenge　for　its　application.　Finally,　we　provide　an　outlook　for　the　development　of　nonlinear　ultrasonic　detection　technology　for　early　degradation　of　bonding　interfaces.