Due　to　the　growing　concern　of　aggravated　environmental　problems　(air　pollution,　global　warming,　etc.)　and　Li　resources,　Na-ion　batteries　have　received　significant　attention　as　a　promising　alternative.　Many　electrode　materials　for　Na-ion　batteries　have　been　reported　in　the　past,　especially　over　the　past　five　years.　However,　most　of　these　materials　have　a　single　crystalline　structure　and　exhibit　a　limited　electrochemical　performance.　Recently,　some　electrode　materials　with　composite　structures　have　been　reported　for　both　Li-ion　and　Na-ion　batteries　and　have　attracted　attention　because　of　their　enhanced　comprehensive　electrochemical　performance.　Herein,　a　detailed　discussion　on　the　development　of　these　composite-structure　materials　for　Na-ion　batteries　is　conducted　based　on　the　crystalline　structure.　The　structure　design,　identification,　and　adjustment　of　these　materials　are　thoroughly　discussed.　Furthermore,　the　future　outlook　based　on　a　mechanism　analysis　and　a　new　electrode-material　structure　system　is　also　introduced　in　this　work,　by　reviewing　previous　important　studies　on　composite-structure　materials.