Better　understanding　the　crystal-facet　engineering　of　a　crystal　with　tailored　architecture　has　demonstrated　a　significant　implication　for　rational　design　and　synthesis　of　promising　micro-/nanostructure.　In　the　past　decades,　extensive　investigations　have　been　devoted　to　the　development　of　cuprous　oxide　(Cu2O)　crystals　with　tailored　architectures,　which　can　provide　a　meritorious　platform　for　not　only　revealing　the　structure-property　performance　relationship　and　but　also　improving　the　performances　in　their　practical　applications.　Several　previous　reviews　have　mainly　reported　the　partial　summaries　of　the　advances　in　facet-dependent　properties　of　Cu2O　crystals.　However,　a　comprehensive　summary　on　Cu2O　crystals　is　lacking　and　highly　desirable　to　further　promote　the　development　of　function-oriented　Cu2O-based　micro-/nanostructures.　In　this　review,　we　will　comprehensively　highlight　the　important　progresses　in　Cu2O　crystals　with　tailored　architectures,　including　the　synthetic　strategies　and　corresponding　growth　mechanisms,　the　fundamental　properties　of　different　crystallographic　facets,　the　functional　modifications　(including　doping　and　hybridization),　and　their　potential　applications.　Several　urgent　issues　and　perspective　are　also　discussed.　(C)　2018　Elsevier　Ltd.　All　rights　reserved.