The　rapid　advancement　of　transmission　electron　microscopy　has　resulted　in　revolutions　in　a　variety　of　fields,　including　physics,　chemistry,　and　materials　science.　With　single-atom　resolution,　3D　information　of　each　atom　in　nanoparticles　is　revealed,　while　4D　electron　tomography　is　shown　to　capture　the　atomic　structural　kinetics　in　metal　nanoparticles　after　phase　transformation.　Quantitative　measurements　of　physical　and　chemical　properties　such　as　chemical　coordination,　defects,　dislocation,　and　local　strain　have　been　made.　However,　due　to　the　incompatibility　of　high　dose　rate　with　other　ultrathin　morphologies,　such　as　nanowires,　atomic　electron　tomography　has　been　primarily　limited　to　quasi-spherical　nanoparticles.　Herein,　the　3D　atomic　structure　of　a　complex　core-shell　nanowire　composed　of　an　ultrathin　Boerdijk-Coxeter-Bernal　(BCB)　core　nanowire　and　a　noble　metal　thin　layer　shell　deposited　on　the　BCB　nanowire　surface　is　discovered.　Furthermore,　it　is　demonstrated　that　a　new　superthin　noble　metal　layer　deposition　on　an　ultrathin　BCB　nanowire　could　mitigate　electron　beam　damage　using　an　in　situ　transmission　electron　microscope　and　atomic　resolution　electron　tomography.　The　colloidal　coating　method　developed　for　electron　tomography　can　be　broadly　applied　to　protect　the　ultrathin　nanomaterials　from　electron　beam　damage,　benefiting　both　the　advanced　material　characterizations　and　enabling　fundamental　in　situ　mechanistic　studies.